Glossary

Numerics

+E.164 alias An international phone number written with a plus sign (+) before the phone number to indicate that the number is in international (E.164) format.

3CCD A technique that determines colors by sending light through a prism, which separates the light into the RGB spectrum frequencies. Each color is measured on an individual light-sensitive chip. Also known as three-chip cameras.

3G-SDI 3G Serial Digital Interface; a video interface that consists of a single 2.970 Gbps serial link that allows you to replace dual-link HD-SDI.

802.11e The standard used for wireless networks. Both 802.1p and differentiated services code point are the standards to set priorities on wired networks. This standard is commonly referred as user priority, and it is important to map the UP to its appropriate DSCP value.

802.1d A Layer 2 protocol known as Spanning Tree Protocol that runs on bridges and switches. The main purpose of STP is to ensure that you do not create loops when you have redundant paths in your network.

802.1p An IEEE standard that allows Layer 2 CoS to be applied from the switch. Eight different classes of service are expressed in a 3-bit PCP field in a q header added to the frame.

802.1Q An IEEE standard often referred to as Dot1Q. It is the networking standard that supports VLANs on an IEEE 802.3 Ethernet network. This standard defines a system of VLAN tagging for Ethernet frames and the accompanying procedures to be used by bridges and switches in handling such frames. The standard also contains provisions for a quality-of-service prioritization scheme commonly known as IEEE 802.1p and defines the Generic Attribute Registration Protocol.

802.1s Multiple Instance Spanning Tree Protocol (MISTP).

802.1w Rapid Spanning Tree Protocol (RSTP).

802.1x A data link layer authentication protocol used by Cisco IP phones to connect to a Cisco Catalyst switch that implements this security mechanism. Phones that support 802.1xmust be configured correctly; otherwise, the data link layer authentication will prevent the phone from registering.

802.3af An IEEE standard for PoE that supports up to 15W of power to any device that supports PoE.

802.3at An IEEE standard also known as PoE+ that can support up to 25.5W of power to any device that supports this standard.

A

AAAA-records A type of lookup record that resolves 128-bit IPv6 addresses to URLs.

AAR Automated alternate routing; a type of routing that automatically reroutes calls through the PSTN or another network when the system blocks a call due to insufficient bandwidth.

absorption The complete dissipation of sound waves within an object of obstruction. Absorption is similar to transmitting through an object.

ACG Automatic gain control; a function that makes dynamic adjustments to gain, typically on a microphone signal, to maintain an optimal level for different speakers.

ACL Access control list; a function of a router that controls ingress and egress traffic based on protocol or port.

acoustical power A measure of amplitude over time.

AD Active Directory; a Microsoft Corporate Directory product used for user and device management and LDAP integrations.

AD forest The topmost logical container in an Active Directory configuration that contains domains, users, computers, and group policies.

ad hoc “On the fly”; a call escalation function through a Cisco Unified Communications Manager allowing a point-to-point call to escalate to a multipoint call using an external conferencing resource to host the call.

AD LDS Active Directory Lightweight Directory Services; an independent mode of Microsoft Active Directory that provides dedicated directory services for applications.

AD tree A collection of domains within a Microsoft Active Directory network. The term refers to the fact that each domain has exactly one parent, leading to a hierarchical tree structure. A group of Active Directory trees is known as a forest.

ADAM Active Directory Application Mode; a part of Microsoft’s fully integrated directory services available with Windows Server 2003 and built specifically to address directory-enabled application scenarios.

ADCS Active Directory Certificate Service; a service that runs on a Microsoft Windows Server. This service can be used to sign private certificates for use within an enterprise.

ADDTS Add Traffic Stream; a message sent from a wireless client that is preparing to place a call to an access point to indicate the TSPEC. The access point can then accept or reject the ADDTS request based on whether bandwidth and priority treatment are available.

Advanced Networking An option key on the Expressway Edge servers that enables a second NIC so that when the Expressway Edge is placed in a DMZ, one NIC can communicate with the internal network and the second NIC can securely communicate with the public Internet. Calls can then be bridged across these two NICs through the Expressway Edge.

AEC Acoustic Echo Cancellation; a method that works by comparing the audio input from a near-end mic against the audio input from a far-end mic and subtracting the common delayed audio.

AI Artificial intelligence.

alert report A Cisco Unified Serviceability report generated on the CUC that contains any alerts that were generated along with their severity.

aliasing A form of distortion caused when a digital signal is converted back to analog form by a digital-to-analog converter; false frequency components appear that were not in the original analog signal.

AMIS Audio Messaging Interchange Specification analog; a protocol that provides a mechanism for transferring voice messages between different voice-messaging systems.

amplitude The measure of the magnitude of change in each oscillation of a sound wave. Most often this measurement is peak-to-peak, such as the change between the highest peak amplitude value and the lowest trough amplitude value, which can be negative.

analog signal A continuous signal that contains a time variable representative of some other time-varying quality, such as the voltage of the signal may vary with the pressure of the sound waves.

ANI Automatic number identification; a service that provides the receiver of a telephone call with the number of the calling phone.

annunciator A device that allows spoken messages or call process tones to be played during a call. They use the SCCP protocol for communication, but they can be used by either SIP or SCCP phones.

aperture The diameter of the hole through which light enters a camera. The size of the aperture controls the amount of light entering your lens to the camera sensors.

API Application programming interface; a set of functions and procedures allowing the creation of applications that access the features or data of an operating system, application, or other service.

application users Users who are associated with Cisco Unified Communications features or applications, such as Cisco Unified Contact Center Express or Cisco Unified CM Assistant. These applications must authenticate with Cisco Unified Communications Manager, but these internal “users”do not have an interactive login and serve purely for internal communications between applications.

A-record A mapping record used by Domain Name Servers to map a URI address to an IP address. A-records consist of a host name and domain name, which make up the URI, and an IP address.

ARP Address Resolution Protocol; the protocol used to map IP network addresses to the hardware MAC addresses used by a data link protocol.

ASR Aggregation Services Router; a type of router used in edge routing for high-bandwidth applications in large enterprise businesses.

assent A protocol that requires two components: a traversal server and a traversal client. The traversal server resides outside the firewall or in a DMZ. The traversal client resides inside the firewall and initiates communication with the traversal server. Ports do need to be opened on the firewall, but they cannot be used unless a communication is initiated from inside the firewall. Only two ports are required to be opened on the firewall because Assent will multiplex the media so all RTP traffic uses one port and all RTCP traffic uses a second port. In addition to the firewall traversal capabilities of Assent, NAT traversal is built into the protocol as well. Also, Assent can be used with both the SIP and H.323 communication standards.

asymmetric cryptography The same process as symmetric cryptography, except that the identity of the communicating parties can be authenticated using public-key cryptography.

autoframing An AI technology built into some of the Cisco Telepresence endpoints that allows individual zoomed-in video switching between participants who are speaking within a video meeting room. Autoframing technology can follow participants in a room using speech detection and facial recognition.

auto-registration A setting in the CUCM that uses a generic template to automatically register all devices that communicate with the TFTP service on the CUCM.

AXL Administrative XML Web Service; an XML/SOAP-based interface that provides a mechanism for inserting, retrieving, updating, and removing data from the Unified Communications configuration database. Developers can use AXL and the provided WSDL to create, read, update, and delete objects such as gateways, users, devices, route patterns, and much more.

B

B2B Shorthand for “business-to-business.”This term refers to sales your business makes to other businesses rather than to individual consumers.

B2BUA Back-to-back user agent; a logical network element in SIP applications. It is a type of SIP UA that receives a SIP request, then reformulates the request, and sends it out as a new request.

B2C Shorthand for “business-to-consumer.”This term refers to sales your business makes to individual consumers rather than to other businesses.

backup device A compilation of settings used to discover the database to which the backup information will be saved.

backup status A table that displays the status of a backup as each component is being backed up.

balanced audio cable A cable that is characterized by three wires, two of which carry the identical signal 180 degrees out of phase with each other. The third is the ground that encompasses the other two wires to protect them from outside noise. This allows for better isolation of the signal from EMI noise.

bandwidth The rate that data bits can successfully travel across a communication path.

Base64-Encoded Format An encoding method for certificates that converts binary to plain ASCII text.

BAT Bulk Administration Tool; a feature of the CUCM that allows administrators to push bulk settings to many phones by using a CSV file.

Bayer A filter within a camera that lets about one-third of each color in and maps the saturation levels of each color per pixel in a mosaic type of effect.

BFCP Binary Floor Control Protocol; the IETF standard for content sharing over SIP.

bidirectional mic A directional mic that picks up equally in two directions, usually 180 degrees opposed.

bit depth The size of a packet sample, which is measured in bits per sample.

BPS Bulk Provision Service; a service that administers and maintains all jobs that are submitted through the Bulk Administration menu of the Cisco Unified Communications Manager Administration.

BRI Basic Rate Interface; an ISDN configuration intended primarily for use in subscriber lines similar to those that have long been used for voice-grade telephony services. This allows BRI connections to use existing telephony infrastructure at businesses. BRI ISDN contains two Bearer channels, or B-channels, and one Delta channel, or D-channel. BRI Bearer channels support 64 kbps bandwidth and are used to carry audio data. The BRI Delta channel supports 16 Kbps and is used to send all the control signaling, such as call setup messaging, call teardown messaging, and timing for TMD.

BRI NT port An NT port found on the BRI Network Termination box. An NT port always connects to a TE port and vice versa.

BRI TE port A TE port found on BRI ISDN Terminals, such as ISDN phones or PBX trunk ports. A TE port always connects to a NT port and vice versa.

C

CA Certificate authority; the certificate server that issues and verifies the authenticity of certificates.

CAC Call Admission Control; a feature on the CUCM that allows the systems in place to control various aspects of voice and video calls over IP, such as bandwidth consumption and QoS across an enterprise network.

call handler A messaging system that allows calls to be routed to specific destinations based on the caller’s input.

call queuing A feature that allows hunt pilot callers to be held in a queue while they wait for an agent to become available. Call queuing is based on the existing call distribution capabilities that are provided by hunt lists and hunt pilots. It enables calls to a hunt pilot to be redirected to a queue if all agents that are associated with the hunt pilot are busy, logged out, unregistered, or do not answer.

call routing A method the CUC employs to handle calls from users in the system, as well as undefined callers from outside the organization.

Call Setup mode An H.323 setting configured on an endpoint that can be set to either Direct or Gatekeeper. If Call Setup mode is set to Direct, the endpoint will never attempt to register to a gatekeeper and will only be able to dial by IP address. When Gatekeeper mode is used, the endpoint is completely subservient to a gatekeeper and will perform no function until it has registered.

CAMA Centralized Automated Message Accounting; a system developed so that billing data can be recorded at a centralized crossbar tandem office for message unit and toll calls originated by telephone customers served by a large number of local dial central offices.

CAPF Certificate Authority Proxy Function; a level of security that performs several tasks depending on your configuration. It can be used to authenticate via an existing manufacturing installed certificate (MIC), locally significant certificate (LSC), randomly generated authentication string, or optional less secure “null”authentication. It issues locally significant certificates to supported Cisco Unified IP phones. It upgrades existing locally significant certificates on the phones. CAPF also retrieves phone certificates for viewing and troubleshooting.

CAPWAP Control and Provisioning of Wireless Access Points; a protocol that enables an access controller to manage a collection of wireless termination points.

CAR Committed access rate; a service that limits the input or output transmission rate on an interface or subinterface based on a flexible set of criteria. Another tool is known as DCAR, or Distributed CAR.

CAR Tool CDR Analysis and Reporting Tool; a tool that uses CDR and CMR data to provide system-generated reports to users, managers, and administrators. These reports can help monitor QoS issues, device utilization, or call statistics.

cardioid mic A directional mic with a pickup pattern shaped like a heart. The mic’s effective pickup area is primarily focused on the area in front and to the sides of the microphone.

CAS Channel Associated Signaling; a form of signaling that is part of the PRI T1 format for ISDN communications.

CAST Cisco Audio Session Tunnel; a proprietary protocol used to split the audio and video media streams between Cisco Jabber and a VoIP phone when using CTI for deskphone control from Jabber.

CBWFQ Class-Based Weighted Fair Queuing; an algorithm that provides class bandwidth guarantees for user-defined traffic classes. It provides flow-based WFQ support for non-user-defined traffic classes.

CCD Charged-couples device; an image sensor that detects variable attenuation of light waves and converts them into electrical current.

CCMCIP Cisco CallManager Cisco IP Phone service; Cisco Jabber requires you to configure a Cisco Unified Communications Manager IP Phone service profile on Cisco Unified Communications Manager to retrieve settings and information about devices that are associated for each user.

CDP Cisco Discovery Protocol; a proprietary protocol used at Layer 2 of the network for device and information discovery across a network.

CDR Call detail records; data records that contain information about each call that was processed by CallManager.

CDR Agent service A service that transfers CDR and CMR files that CUCM generates from the local host to the CDR Repository node, where the CDR Repository Manager service runs over an SFTP connection.

CDR Repository Manager service A service that maintains the CDR and CMR files, allocates the amount of disk space for use by CMRs and CDRs, sends the files to up to three configured destinations, and tracks the delivery result for each destination.

CDR Repository node CUCM node where CDR and CMR files are stored.

CE Collaboration Endpoint; software that comes preloaded onto DX, MX, SX, and WebEx endpoints. This software is based on the legacy TC software.

CEC Consumer Electronics Control; a feature used to set the screen in standby when an endpoint itself enters standby. Likewise, the system will wake up the screen when the system itself wakes up from standby.

cell boundary overlap The primary mechanism for providing RF high availability. In general, a cell boundary overlap of 20 to 30 percent on nonadjacent channels is recommended to provide high availability in the wireless network.

CER Cisco Emergency Responder; a database server that enhances the existing emergency 9-1-1 functionality of the Cisco Unified Communications Manager by ensuring it will send emergency calls to the appropriate Public Safety Answering Point (PSAP) for the caller’s location and that the PSAP can identify the caller’s location and return the call if necessary.

chrominance A measurement of the color spectrum in light.

CIF Common intermediate format; a video format designed by the ITU as a compromise between NTSC and PAL resolutions for digital video transmission, particularly regarding video communication.

Cisco Precision Video Engine Technology embedded into the Cisco Jabber soft client that uses specialized compression algorithms to offer higher-quality video over lower bandwidth. This technology is what makes HD call capability possible in the Jabber client.

Cisco Unified Serviceability A service and reporting tool available on the Cisco Unified Communications Manager, Cisco Unified IM and Presence server, and Cisco Unity Connection.

Cisco Unity Connection Serviceability A reporting tool available only through the Cisco Unity Connection server that allows for 20 different reports to be generated.

classification pulse A “first detection”pulse sent from a PSE to a device to determine whether the device is powered or not.

CleanAir A Cisco technology used to increase the WLAN reliability by detecting radio frequency interference in real time and providing a self-healing and self-optimizing wireless network.

ClearPath technology Special algorithms applied at the codec to incoming video that clarifies the video quality by adding pixels to the image. There is no extra bandwidth cost to using ClearPath technology, but the image quality is greatly improved.

CLI Command-line interface; a text-based command structure that allows an administrator to interact with a system. CLI can be used over an IP connection or through a console connection.

clipping A form of distortion that occurs when a signal exceeds the maximum dynamic range of an audio channel.

cluster-level backup A backup of all servers in a cluster collected in a central location and archived to a physical storage device.

CMA Cisco Meeting Application; a softphone application based on the WebRTC protocol that works with Cisco Meeting Server.

CMC Client Matter Codes; a feature that forces the user to enter a code to specify that a call relates to a specific client matter. You can assign client matter codes to customers, students, or other populations for call accounting and billing purposes.

CME Communications Manager Express; a Cisco Unified application that provides call processing to Cisco Unified IP phones for distributed enterprise branch-office environments. Cisco Unified CME delivers on this need by providing localized call control, mobility, and conferencing alongside data applications on Cisco ISRs.

CMOS Complementary metal-oxide-semiconductor; an image sensor that detects variable attenuation of light waves and converts them into electrical current.

CMR Call management records; data records that contain quality of service or diagnostic information about the call. Also referred to as diagnostic records.

CMS Cisco Meeting Server; an on-premises conferencing server used for rich media multipoint conferencing between three or more participants.

CN Common Name; a subcategory in an LDAP hierarchical tree used to categorize users or devices within an organization.

COBRAS Consolidated Object Backup and Restore Application Suite; a tool used to migrate the legacy Cisco Unity server settings into the Cisco Unity Connection server platform.

codec A conjunction of the words coding and decoding; the hardware or software that codes and decodes audio and video data. Codec also refers to the standards that outline how the coding and decoding operates.

codec preference list A list that allows the router to act as a demarcation point on a VoIP network and allows a dial peer to be established only if the desired codec criteria are satisfied. Preferences can be used to determine which codecs will be selected over others.

coherent late reflections Sound wave reflections from surfaces that stand out from normal reverberation levels; they are the ones we typically identify as echoes. In this case, the arrival of the late reflection sound waves passes a certain millisecond tolerance and is perceived as a second sound rather than the prolonging of the first sound.

compliance A function of Cisco IMP that allows the storing of instant messages on an external server or database for archiving.

component video A video signal split into two or more component channels.

composite video Video information combined into a single line level.

compression One of the link efficiency mechanisms that work in conjunction with queuing and traffic shaping to manage existing bandwidth more efficiently and predictably. There are two types of compression available. See also stacker and cRTP.

condenser mic A type of mic that operates on electrostatic principles in which two conductive plates in close proximity to each other exchange a charge as the plates vibrate. This operation requires that an external power source be used to supply the charging voltage to element, usually in the form of phantom power.

conferencing Mixing multiple streams (three or more) to create one output stream.

congestion avoidance An effect achieved through packet dropping. Congestion avoidance mechanisms monitor network traffic loads in an effort to anticipate and avoid congestion at common network bottlenecks.

congestion management The use of markings on a packet to determine in which queue to place it. Different queues are given different treatment by the queueing algorithm that is based on the class of packets in the queue. Generally, queues with high-priority packets receive preferential treatment.

corporate directory A phonebook that an endpoint subscribes to when an entry needs to be looked up. These directories do not live on the endpoint itself; rather, they exist solely on the system designed to deliver the aliases when requested.

CoS Class of service; a Layer 2 QoS mechanism that operates on the 802.1q VLAN. CoS is used to mark packets at the Layer 2 switch port and create trust boundaries so that phones and other trusted devices can mark their own QoS packets.

CoS (on CUC) Class of service; in this context, the term describes which features the Cisco Unity Connection users have permission to use.

COS Cost of service; a mechanism in the CUCM that is used to control telephony charges by blocking costly service numbers and international calls for some users. COS is also used to protect the privacy of some users, such as to disallow direct calls to managers except through their assistants.

CQ Custom queuing; a function that guarantees some level of service to all traffic because you can allocate bandwidth to all classes of traffic. You can define the size of a queue by determining its configured packet-count capacity, thereby controlling bandwidth access.

critical distance The distance between a person who is speaking and a microphone as it relates to other active mics. A good rule of thumb is a 1:3 ratio. If the person speaking is 3 feet from the target mic, the next closest mic should be no closer than 9 feet.

CRT Cathode Ray Tube; the old analog style of monitor, which is no longer in use.

cRTP Compressed RTP; a link efficiency compression algorithm that can compress the IP, UDP, and RTP headers down from 40 bytes to 2–4 bytes.

CSF Cisco Unified Client Services Framework; a phone template that registers the softphone with Cisco Unified Communications Manager as a SIP device.

CSR Certificate signing request; a template used to submit information to a CA so that a certificate can be signed.

CSS Calling search spaces; a classification that defines which partitions are accessible to a particular device within the CUCM.

CSV Comma-separated values; a simple file format used to store tabular data, such as a spreadsheet or database. Files in the CSV format can be imported to and exported from programs that store data in tables, such as Microsoft Excel or OpenOffice Calc.

CTI Computer Telephony Integration; a technology that enables computer and telephone systems to interact together.

CTI port A virtual port that is analogous to a trunk line in a traditional ACD or PBX setting.

CTI route point A virtual device that can receive multiple simultaneous calls for the purpose of application-controlled redirection.

CTIQBE Computer Telephony Interface Quick Buffer Encoding; a protocol used by TAPI and other Cisco services to communicate with the CUCM.

CTL Certificate trust list; a certificate file sent from a CUCM to an endpoint to establish a trust between that device and the CUCM for secure communication. The CTL file contains a server certificate, public key, serial number, signature, issuer name, subject name, server function, DNS name, and IP address for each server.

CUBE Cisco Unified Border Element; a service that runs on Cisco routers to provide TURN services into and out of an enterprise network.

CUC Cisco Unity Connections; a unified messaging and voicemail solution within Cisco’s Collaboration suite of products.

CUCL Cisco User Connect Licensing; per-user based licensing for individual Cisco Unified Communications applications, including the applications server software, user licensing, and a soft client. User Connect Licensing is available in Essential, Basic, Enhanced, and Enhanced Plus versions.

CUCM Cisco Unified Communications Manager; a platform that provides reliable, secure, scalable, and manageable call control and session management.

CUCSF Cisco Unified Client Services Framework; the framework used to support the Cisco Jabber soft client application.

CUE Cisco Unity Express; a tool that offers industry-leading integrated messaging, voicemail, fax, automated attendant, interactive voice response, time-card management, and a rich set of other messaging features on the Cisco Integrated Services Router platform.

current logging A list of current available logs on a CE software-based endpoint since the last reboot of the endpoint.

CUWL Cisco Unified Workspace Licensing; a communications and video solution that provides the most popular Cisco Collaboration applications and services in a cost-effective, simple package. Two Cisco Unified Workspace Licensing offers are available, depending on your needs: Professional Edition and Standard Edition. Professional Edition includes comprehensive, unlimited participant video conferencing with Personal Multiparty video at no additional cost.

D

data compression A reduction in the amount of bandwidth consumed from the total transmission capacity. Compression involves utilizing encoding algorithms to reduce the size of digital data.

data VLAN A VLAN partition used for grouping common data usage, such as emails and web searching.

DC Domain controller; the main domain under which all categories in an LDAP hierarchical tree reside for an organization.

depth of field A camera effect that refers to the objects, from nearest to farthest, that are in sharp focus of a camera’s lens. The size of the depth of field is a function of focal length and Iris. On cameras equipped with an iris, the depth of field can be extended by decreasing the aperture.

DER encoded format Distinguished Encoding Rules encoded format; a binary format used with certificates.

Deskphone mode A mode in which the Cisco Jabber client controls the Cisco IP phone of the user. For an IP phone without a camera, the video input and output are processed on the Cisco Jabber client platform but the voice input and output are processed on the IP phone. This split media is performed using CAST.

DHCP Dynamic Host Configuration Protocol; an open-source protocol used by network devices to automatically discover network addressing information so that communication across the network is possible. The DHCP process is a four-step process that involves discovery, offer, request, and acknowledgment.

dial peer A concept that Cisco IOS XE routers use to route calls. Every call that traverses through the router has to match an inbound dial peer and an outbound dial peer.

dial plan A carefully planned design for reaching devices and services in a Collaboration network and in the PSTN.

DID Direct inward dialing; a service that maps PSTN E.164 numbers directly to an IP phone behind a PBX.

Diffie-Hellman Key Exchange A method of securely exchanging cryptographic keys over a public channel; it was one of the first public-key protocols.

DiffServ A QoS network design model that operates on classes that require special QoS treatment.

diffusion The process of dispersing radiated energy so that it is less direct or coherent. It is caused by sound waves reflecting off many complex surfaces.

digital signal A continuous quantity of samples that is a representation of a sequence of discrete values that can take on only one of a finite number of values.

digit-by-digit analysis A method of addressing used exclusively by SCCP phones. When the phone goes “off hook,”a message is sent to the Cisco Unified Communications Manager. The CUCM will analyze every keypress or action of the SCCP phone until a successful match is found.

direct sound The first and primary sound waves that hit your ears.

directional mic A microphone with a polar pickup pattern intended for pointing at a more selective group of audio sources.

directory A centralized enterprisewide datastore used for the storage of information about individuals within an enterprise.

directory schema A plan that defines the type of information stored, its container (or attribute), and its relationship to users and resources.

Directory URI A unique Uniform Resource Identifier on the CUCM, similar in nature to a standard URI, that takes the form of User@domain or User@IP. The Domain part of the Directory URI is also referred to as the Host part of the URI.

DirSync A service on the CUCM that is used to enable the Directory Synchronization function.

Discovery mode A mode in which an endpoint will locate the gatekeeper to which it will attempt to register. Discovery mode can be configured to either Automatic or Manual.

distance factor The ability of a microphone to pick up sound from a distance as related to two different types of microphones,such as a handheld microphone and an omnidirectional mic.

distribution list (CUC) A list in CUC that is used to send voice messages to multiple users. The users who are members of a system distribution list are typically those who need the same information on a regular basis, such as employees in a department or members of a team.

DMVPN Dynamic Multipoint Virtual Private Network; a solution that provides an alternative to the complicated administrative setup and maintenance that comes with establishing a mesh network. Initially, the DMVPN is set up as a hub-and-spoke network. After communication is established between the spokes and the hub, each spoke will dynamically discover each of the other spokes and establish a tunnel between one another.

DMZ Demilitarized zone; a perimeter network or screened subnet security solution. It is a physical or logical subnetwork that contains and exposes an organization’s external-facing services to an untrusted, usually larger, network such as the Internet.

DN Directory number; a unique number assigned to a phone from the CUCM that can be used to call into that phone. DNs are similar in nature to an E.164 address.

DNA Dialed Number Analyzer; a tool on the CUCM that allows the administrator to analyze call flows through the CUCM by simulating call attempts.

DND Do Not Disturb.

DNIS Dialed Number Identification Service; a service offered to companies by PSTN carriers that identifies the originally dialed telephone number of an inbound call. Companies may use this information for call routing to internal destinations or activation of special call handling.

DNS Domain Name System; a type of service that allows URL addresses to be used in place of IP addresses. DNS will resolve the URLs to their IP address mapping.

DS0 A signal introduced to carry a single digitized voice call. For a typical phone call, the audio sound is digitized at an 8 kHz sample rate using 8-bit pulse-code modulation for each of the 8000 samples per second. This results in a data rate of 64 kbps.

DS1 A signal in which 24 DS0s are multiplexed. To limit the number of wires required between two destinations that need to host multiple calls simultaneously, a system was built in which multiple DS0s are multiplexed together on higher-capacity circuits.

DS3 A signal in which 28 DS1s are multiplexed. To limit the number of wires required between two destinations that need to host multiple calls simultaneously, a system was built in which multiple DS0s are multiplexed together on higher-capacity circuits.

DSCP Differentiated services code point; a Layer 3 QoS classification for marking packets.

DSP Digital signal processor; a card used in Cisco routers to provide software- and hardware-based media resources.

DTMF Dual-tone Multifrequency signaling; an in-band communications system that has been used for many years by telephone companies, which allows end users to communicate by pressing keys on their phone.

DuoVideo A Tandberg proprietary protocol for content sharing.

DV certificate Domain validation certificate; a type of certificate in which the CA only checks the right of the applicant to use a specific domain name. No company identity information is vetted, and no information is displayed other than encryption information within the Secure Site Seal.

DX Desktop Experience; a branding type for Cisco Telepresence endpoints that offers a personal Telepresence desktop endpoint for customers.

dynamic range A range of amplitudes that can be accurately captured by the microphone. This is usually represented in decibels at a certain frequency, typically 1 kHz.

E

E&M Receive and Transmit, also referred to as Ear and Mouth; ports for an analog trunk connection to a legacy PBX system.

E.164 Alias Numeric-only values containing 1–15 digits that are assigned to an endpoint. They work in the same manner as any phone number would in a typical telephony environment.

early reflections Sound waves that bounce off but arrive at your ears at almost precisely the same time as the direct sound coming from the sound source.

EIGRP Enhanced Interior Gateway Routing Protocol; an advanced distance-vector routing protocol that is used on a computer network for automating routing decisions and configuration. The protocol was designed by Cisco Systems as a proprietary protocol, available only on Cisco routers.

electronic filters Filters used to help remove unwanted frequency, or noise, from an analog signal.

EMR Electromagnetic radiation; different spectrums of light.

en bloc A type of dialing in which the whole dialed string is sent in a single SIP INVITE message.

end users Users who are associated with a physical person and an interactive login. This category includes all IP telephony users as well as Cisco Unified Communications Manager administrators when using the user groups and roles configurations.

endpoint An audio-only or audio- and video-capable device used for communication.

enterprise parameters Factors used to define clusterwide system settings; these parameters apply to all devices and services across all nodes within the entire cluster.

Euroblock European-style terminal block; a low-voltage connector and terminal block combination commonly used for microphone- and line-level audio signals and for control signals such as RS-232. It is also known as the Phoenix connector from one of the manufacturers, though many manufacturers make compatible products. The Euroblock is a solderless connector that uses screw terminals to clamp connecting wires. After the wires are installed, the entire assembly is plugged into a matching socket in the electronic device. Euroblocks are more convenient than the terminal strips they replace because the signal cables can be quickly disconnected from or connected to the electronic device so that you don’t have to unscrew and rescrew each wire individually.

EV certificates Extended validation certificates; certificates that the certificate authority uses to check the right of an applicant to use a specific domain name; in addition, it conducts a thorough vetting of the organization.

eventlog A folder, also included in the current folder, that contains a directory of log files that offer more verbose information.

Extended Logging A setting on CE software-based endpoints that sets a higher level of debug on the system in order to capture deeper log traces from endpoint activity. There are three levels to extended logging. Start Extended Logging enables debugs, including SIP Tracing, and lasts for 10 minutes. Include Limited Packet Capture enables the same as above, plus a packet capture of the signaling during call setup and teardown but no media, and will last for 10 minutes. Include Full Packet Capture includes all the above plus media packet capture but lasts for only 3 minutes.

F

FAC Forced authorization code; a method used to restrict access to users who know a code needed to place offnet calls.

FECC Far-end camera control; the ability of an endpoint’s camera to be controlled using PTZ from a far-end endpoint while in a call.

field of view The width and height of an image captured by a camera.

FIFO First-in, first-out; a method that performs no prioritization of data packets on user data traffic. It entails no concept of priority or classes of traffic. When FIFO is used, ill-behaved sources can consume available bandwidth, bursty sources can cause delays in time-sensitive or important traffic, and important traffic may be dropped because less important traffic fills the queue.

firewall A system that exists to protect the inside of a corporate network from outside attack. The purpose of a firewall is to control IP traffic entering your network. Firewalls generally block unsolicited incoming requests, meaning that any communication originating from outside your network will be prevented. However, firewalls can be configured to allow outgoing requests to certain trusted destinations, and to allow responses from those destinations. Allowing traffic in both directions prevents the firewall from doing its job.

Flex Cisco Collaboration Flex Plan; a subscription-based offer that entitles people to use Cisco’s industry-leading collaboration tools. It helps with transitions to the cloud and investment protection by including cloud, premises, hosted and hybrid deployments, with the flexibility to use them all.

Foveon X3 sensors Sensors that use a method similar to how color film for photography works. An array of layered pixel sensors separates light via the inherent wavelength-dependent absorption property of silicon, such that every location senses all three color channels.

FQDN Fully qualified domain name; a domain that has been qualified against an authority, such as the Cisco Expressway or a publicly registered DNS address.

frame A still image. Each still image in a series, known as a reel, is a separate frame.

frame rate The number of frames that are shown per second, or fps.

frequency The rate of air pressure fluctuation produced by an acoustic energy wave.

frequency response The range of frequencies accurately captured.

frequency spectrum The complete range of frequencies audible to the ear.

FRTS Frame Relay Traffic Shaping; a QoS shaping tool used on output interfaces to help smooth out mismatches in the network and limit transmission rates.

FTP File Transfer Protocol; a protocol used to transfer large files between a server and a client. A secure transmission can also be established using SFTP.

FXO Foreign eXchange Office; an interface that receives POTS service, typically from a central office of the public switched telephone network.

FXS Foreign eXchange Subscriber; an interface that delivers POTS service from the local phone company and must be connected to subscriber equipment.

G

gain The ability of a system to adjust the power or amplitude of a signal between the input and the output of a given circuit. Gain can be in the form of amplification or attenuation in either a digital or analog process; no change in the signal as it passes through is called unity gain or simply unity.

gatekeeper A call control device used with H.323. Gatekeepers provide registration, security, and call control in an otherwise unsecure and uncontrolled environment.

gaze angle Based on the position of a camera to the display, an angle that allows a participant in a room to look a far-end participant in the eye, or at the display, and still maintain eye contact with the far-end participant on the display.

GLBP Gateway Load Balancing Protocol; a Cisco proprietary protocol that offers gateway redundancy. This protocol was designed to overcome the limitations with HSRP and VRRP. It protects data traffic from a failed router or circuit, while also allowing packet load sharing between a group of redundant routers.

global directory A phone book that originates on a server outside of the endpoint itself that is pushed out to the endpoint, so the directory entries live on the endpoint just as the local directory entries live on the endpoint.

good levels A modifier that identifies an audio signal that is significantly higher than the noise floor (good S/NR) but not so strong as to cause clipping and may also indicate leaving appropriate headroom.

group A prioritized list of one or more call-processing servers within Cisco Unified Communications Manager. Cisco Unified Communications Manager Groups are used to collect servers within a cluster that run the Cisco CallManager service in order to provide call-processing redundancy.

GRQ Gatekeeper Request; a RAS broadcast message initiated by an endpoint and used to locate a gatekeeper within the broadcast domain. The gatekeeper to respond will send a GCF, or Gatekeeper Confirm.

GTS Generic Traffic Shaping; a QoS shaping tool used on output interfaces to help smooth out mismatches in the network and limit transmission rates.

GUI Graphical user interface; in this context, a method of visually checking a voice mailbox through the Cisco Unity Connection server.

H

H.224 The standard for far-end camera control.

H.239 The H.320 and H.323 standard for content sharing.

H.245 The process used in H.323 for capability set exchange, master/slave negotiation, and opening logical channels, or ports. H.245 is also responsible for closing logical channels at the end of the call.

H.261 The minimum standard that must be used and was the first of the ITU video codecs. This codec will support QCIF and CIF formats; it uses 64 kbps to 2 Mbps of bandwidth to transmit and receive video. This standard is usually utilized only by legacy devices.

H.263 The standard that came out after H.261 and offers superior advantages. H.263 has better compression, especially in the lower bitrate range, and uses basically the same bandwidth. H.263 also offers support for SQCIF 4CIF and 16CIF at a little less than 30 fps, hence a crisper image.

H.264 The standard sometimes called MPEG-4; it came out at a time when HD communication was being more readily used. This standard was created by the ITU in cooperation with the International Organization for Standardization (ISO) and the International Electrotechnical Commission. It currently is most often used for high-definition video. It is based off MPEG-4 and delivers video that is at the same quality as H.263. The reason it is so favored currently is its capability to deliver video at half the bandwidth usage as H.263.

H.265 HEVC A high-efficiency video codec; it is a draft compression standard ratified in 2013. It’s a logical successor to H.264 AVC, aimed at reducing bitrate significantly due to the complexity of mathematical calculations; and it leverages new compression and prediction techniques.

H.320 An ITU umbrella standard that encompasses many other standards for circuit-switched communication.

H.323 An ITU umbrella standard for packet-switched communication.

H.323 ID An alias that can use any combination of numbers, letters, and/or special characters, but spaces are not allowed. Because of this capability, an H.323 ID can be in the form of a URI. However, an H.323 ID is not a URI because it is not dependent on the domain being a fully qualified domain name.

H.460.17 An H.323 firewall and NAT traversal standard that performs firewall traversal by carrying the media over TCP ports instead of UDP.

H.460.18 An H.323 firewall and NAT traversal standard that works just like Assent, except it requires demultiplexed ports 50000 to 52400 to be opened on the firewall.

H.460.19 An H.323 firewall and NAT traversal standard that works as a layer on H.460.18 to allow multiplexing the media ports so that only two ports need to be opened for RTP and RTCP media streams.

HCS Hosted Collaboration Solution; a cloud offering for Cisco Collaboration through service providers.

HDMI High-Definition Multimedia Interface; an audio and video interface for transmitting uncompressed video data and compressed or uncompressed digital audio data from an HDMI-compliant source device to a compatible display. HDMI is a digital replacement for analog video standards.

HD-SDI High-Definition Serial Digital Interface; an interface that consists of a pair of SMPTE 292M links. It provides a nominal 2.970 Gbps interface used in applications that require greater fidelity and resolution than standard HDTV can provide.

headroom A safety zone for unintended peaks in a signal. It becomes particularly important when a signal may go through several opportunities for gain adjustment within a given system. Microphones, mixers, and amplifiers should be adjusted to always allow adequate headroom to avoid clipping.

historical log A compressed folder containing all the current logs on a CE software-based endpoint designed to send to a Cisco TAC agent over email or file share. Historical logs are created each time the endpoint is rebooted.

HSRP Hot Standby Router Protocol; a Cisco proprietary protocol that provides a fault-tolerantdefault gateway in the event the primary default gateway should fail.

HTTP Hypertext Transfer Protocol; the underlying protocol used by the World Wide Web. This protocol defines how messages are formatted and transmitted, and what actions web servers and browsers should take in response to various commands.

HTTPS Secure Hypertext Transfer Protocol; an extension of the Hypertext Transfer Protocol. It is used for secure communication over a computer network and is widely used on the Internet.

HTTPS Reverse Proxy Cisco MRA settings that provide a mechanism to support visual voicemail access, contact photo retrieval, Cisco Jabber custom tabs, and other data applications.

Hub_None A sample location that typically serves as a hub linking two or more locations. It is configured by default with the Unlimited intralocation bandwidth allocations for audio, video, and immersive bandwidth, but you can specify bandwidth allocations for each of these. By default, devices not assigned to other locations are assigned to Hub_None automatically.

hunt exhaustion A status in the CUCM that occurs after hunting has tried the last line-group member and there were no other line-group members or other line groups to be used.

hunting The capability to route or reroute a call to a group of users within the CUCM so that calls are not just dropped when the originally intended target is not reached.

hypercardioid mic A directional mic that has a narrow focal range, so a larger lobe at the rear of the mic develops.

I

ICANN Internet Corporationfor Assigned Names and Numbers; an organization that has been managing IP addresses and domains since 1998.

ICE Interactive Connectivity Establishment; a framework that pulls together a number of different techniques such as TURN and STUN; it provides a mechanism for SIP client NAT traversal. It allows clients residing behind NAT devices to discover paths through which they can pass media, verify peer-to-peer connectivity via each of these paths, and then select the optimum media connection path. The available paths typically depend on any inbound and outbound connection restrictions that have been configured on the NAT device.

IDD International Direct Dialing; a trunk prefix, also called an international call prefix or dial-out code, used to select an international telephone circuit for placing an international call.

Identity Management A system that involves the management of individuals and the authentication and authorization of these individuals.

IDS Informix Dynamics Server; an IBM-based database management system.

IEEE Institute of Electrical and Electronics Engineers; an association that controls communication using packet-switched technology.

IETF Internet Engineering Task Force; an open standards organization that develops Internet standards.

IM Instant messaging; a text-based communications tool that allows real-time text messages to be sent over the Internet.

IM forking A process by which an end user sends an instant message to a contact who is signed into multiple IM clients, and Cisco IMP Service delivers the instant message to each client. Cisco IMP Service continues to fork instant messages to each client until the contact replies. After the contact replies, Cisco IMP Service only delivers instant messages to the client on which the contact replied.

IMAP Internet Message Access Protocol; an Internet standard protocol used by email clients to retrieve email messages from a mail server over a TCP/IP connection. IMAP is defined by RFC 3501.

IME Intercompany Media Engine; a Cisco network management application that provides system health, events, and collaboration monitoring in addition to reporting and configuration for up to 10 sensors. IME monitors sensor health using customizable dashboards and provides security alerts through RSS feed integration from Cisco Security Center.

IMP IM and Presence; the Cisco Unified Communications Manager IM and Presence Service that provides native standards-based, dual-protocol, enterprise instant messaging, and network-based presence as part of Cisco Unified Communications.

IMS Identity Management System; an internal library inside the CUCM that is used to challenge both end user and application user authentication when services try to log in.

inductive loop An electromagnetic communication or detection system that uses a moving magnet or an alternating current to induce an electric current in a nearby wire. Induction loops are used for transmission and reception of communication signals, or for detection of metal objects in metal detectors or vehicle presence indicators.

Intelligent Proximity for Content Sharing A Cisco proprietary protocol, also referred to as simply Intelligent Proximity, that uses an ultrasonic audio tone, unheard by the human ear, that pairs the endpoint with the Intelligent Proximity application. This application can be installed on a smartphone, tablet, Mac computer, or Windows computer. Once paired, the application will use a Wi-Fi signal, which must be on the same network as the endpoint, to establish communication. Then the Intelligent Proximity app can be used to view and select participants to call from the directories on the endpoint, launch calls, answer incoming calls, and view content being shared during a call. You can scroll back and view previously shared information even when the presenter is sharing something different, and you can take snapshots of the content to peruse after the call ends. When using Intelligent Proximity from a Mac or Windows computer, you can also share content through the application.

Intelligent Proximity MV Intelligent Proximity for Mobile Voice; a service in some Cisco IP phones that brings the worlds of deskphone and mobile phone together. You can move the audio path over to the Cisco IP Phone 8851 during active mobile calls to take advantage of its superior audio acoustics. You also can share contact information from a mobile phone to the deskphone for ease of call placement. Intelligent Proximity MV uses Bluetooth technology for audio and contact sharing.

interlaced scanning A scanning process by which pixels are populated within a frame working from top to bottom, left to right. Odd lines and even lines are populated separately on alternating frames.

intersite routing A type of call-routing that occurs between multiple sites. A translation pattern is used for both centralized and distributed call-processing deployment models.

IntServ A QoS network design model that uses RSVP to guarantee predictable behavior on the network for applications that have specific bandwidth and delay requirements.

IOS XE Internetworking Operating System XE; a combination of a Linux kernel and a monolithic application that runs on top of this kernel. IOS is a monolithic operating system that runs directly on the hardware itself.

IP VMS IP Voice Media Streaming Service; a Cisco Unified Communications Manager service that provides software-based media resources.

IPP IP Precedence; a Layer 3 QoS classification for marking packets.

IPsec V3PN IP Security Virtual Private Network; a network that integrates three core Cisco technologies: IP Telephony, QoS, and IPsec VPN. The result is an end-to-end VPN service that can guarantee the delivery of latency-sensitive voice and video communications.

ISDN Integrated Services Digital Network; a network that is similar to POTS, but the original analog signal is converted to digital format before it is sent across a wire. That digital signal must be converted back to analog at the receiving phone. ISDN uses time-division multiplexing to send the digital signals across the copper wire.

ISR Integrated Services Router; a Layer 3 Cisco router that provides many other services than a typical Layer 3 router.

ITL Identity Trust List; a certificate of authentication that allows the phone to verify that the configuration file came from a trusted source. ITLs by themselves use asymmetric cryptography to authenticate the identity of the server.

ITU International Telecommunication Union; a specialized agency of the United Nations that is responsible for standardizing communication technologies.

ITU BT.709 A standard that defines the color space, resolutions, and frame rates of widescreen high-definition television using the 16:9 aspect ratio.

ITU-R BT.601 A standard that defines the color space, resolutions, and frame rates for encoding interlaced analog video signals into digital video form. A signal that conforms to the BT.601 standard can be regarded as if it is a digitally encoded analog component video signal.

IVR Interactive Voice Response; an auto attendant of sorts that allows a caller to enter the destination alias of the intended target after an initial number has been dialed.

IX Immersive Experience; a branding type for Cisco Telepresence endpoints that offers an in-room immersive endpoint for premium quality collaboration. This is the only Cisco Telepresence endpoint that does not run the CE software. Rather, it runs an older version of CTS software.

J

Jabber A soft client tool that includes the most commonly used Cisco UC tools in a single software package.

Java MIDlets Applications on Cisco IP phones that allow more sophisticated application capabilities such as animated graphics, custom user interface objects, advanced network connectivity, and persistent local storage.

jitter A delay that is similar to latency; however, jitter is a variable of the latency that occurs over a period of time.

JSON JavaScript Object Notation; a lightweight data-interchange format or text format that is completely language independent but uses conventions that are familiar to programmers of the C-family of languages, including C, C++, C#, Java, JavaScript, Perl, Python, and many others. These properties make JSON an ideal data-interchange language.

K–L

KEM Key Expansion Module; a side card that attaches to supported phones and increases the number of lines supported on that phone.

KPML Key Press Markup Language; an XML notation that allows digits to be sent one by one, similar to digit-by-digit analysis. Unlike NTE, which is an in-band method of sending DTMF, KPML uses the signaling channel (out-of-band, or OOB) to send SIP messages containing the DTMF digits. KPML procedures use a SIP SUBSCRIBE message to register for DTMF digits. The digits themselves are delivered in NOTIFY messages containing an XML-encoded body.

LAN Local-area network; a network within a single confined area.

latency The delay packets experience when traversing across many different network devices.

LCD Liquid crystal display.

LDAP Lightweight Directory Access Protocol; a search protocol used most commonly for extracting user information from a corporate directory.

LDAP authentication A process that enables the IMS library to authenticate user credentials of LDAP-synchronized end users against a corporate LDAP directory using the LDAP standard Simple_Bind operation.

LDAP Manager Distinguished Name An LDAP setting in the CUCM where an LDAP manager account from the LDAP database should be specified. To import the data into the Cisco Unified Communications Manager database, the system performs a bind to the LDAP directory using the account specified in the configuration as the LDAP Manager Distinguished Name and reading of the database is done with this account.

LDAP synchronization A process that uses an internal tool called Cisco Directory Synchronization, or DirSync, on the Cisco Unified Communications Manager to synchronize a number of user attributes from a corporate LDAP directory.

LED Light-emitting diode; a semiconductor light source that emits light when current flows through it.

LFI Link Fragmentation and Interleaving; a tool that can reduce delay and jitter on slower-speed links by breaking up large data packets and interleaving low-delay traffic packets with the resulting smaller packets. LFI is typically used on slow WAN links to ensure minimal delay for voice and video traffic.

line level The output of any device with an internal pre-amplifier.

link efficiency Methods used to reduce the overhead that is associated with voice and video transportation. These bandwidth-saving mechanisms, such as compression, link fragmentation, and interleaving, help support large amounts of traffic over a slower link.

LLDP-MED Link Layer Discovery Protocol-Media Endpoint Discovery is an open-source protocol that can be used cross-vendor at Layer 2 of the network for device and information discovery across a network.

LLQ Low-Latency Queueing; a congestion management mechanism developed by Cisco to bring strict priority queuing to Class-Based Weighted Fair Queuing. LLQ allows delay-sensitive data, such as voice and video, to be given preferential treatment over other traffic by letting this data be dequeued and sent first.

Local Agent A service that runs backup and restore scripts on the server. In a cluster, the Local Agent runs backup and restore scripts on each node in the cluster.

local directory A collection of aliases that have been saved directly on the endpoint itself.

local route group A group within a route plan that can decouple the location of a PSTN gateway from the route patterns that are used to access the gateway.

location The aspect of CAC on the CUCM that determines the amount of total bandwidth available for all calls within a particular site, or between sites. When a call is set up, the regional value for that call must be subtracted from the total bandwidth allowed for that site.

lossless A compression algorithm that searches content for statistically redundant information that can be represented in a compressed state without losing any original information.

lossy A compression algorithm that searches for nonessential content that can be deleted to conserve storage space.

luminance A measurement of the brightness of light.

LWAP Lightweight Access Point; a wireless access point device that can be controlled by a wireless controller using LWAPP.

LWAPP Lightweight Access Point Protocol; a protocol that allows multiple Wi-Fi wireless access points, called LWAPs, to be controlled all at once from a single management device, called a wireless controller, including configuring, monitoring, or troubleshooting.

M

macroblock A division of units that are a collection of pixels generally 16×16 in size but can be divided into 8×8 and 4×4 sizes as well.

manual backup A backup that is initiated by an administrator and starts immediately.

Master Agent A service that stores systemwide component registration information, maintains a complete set of scheduled tasks in an XML file, and updates this file when it receives updates of schedules from the user interface. The Master Agent sends executable tasks to the applicable Local Agents, as scheduled. The Local Agents execute immediate backup tasks without delay. The Master Agent stores backup data on a local attached drive or at a remote network location.

media resource A software-based or hardware-based entity that performs media processing functions on the data streams to which it is connected.

mic level The level of voltage that comes out of a microphone when someone speaks into it is known as the microphone level signal, or mic level (–60 dBV to –40dBV). Because mics are self-contained, they produce a much smaller signal than amplifiers, which needs to be treated differently by the device that receives its signal. This is why devices, such as endpoints, have mic level settings and line level settings.

millibar 100 pascals.

MIMO Multiple Input and Multiple Output; a method for multiplying the capacity of a radio link using multiple transmission and receiving antennas to exploit multipath propagation. MIMO has become an essential element of wireless communication standards including IEEE 802.11n, 802.11ac, HSPA+ (3G), WiMAX (4G), and Long Term Evolution (4G LTE). More recently, MIMO has been applied to power-line communication for three-wire installations as part of ITU G.hn standard and HomePlug AV2 specification.

MOH Music On Hold; streaming music to callers on hold.

mono The audio signal played when only one channel is used for both left and right speakers.

MPLS Multiprotocol Label Switching; a transport protocol that uses labels to route traffic rather than network addresses. Packets are forwarded based on the content of the label, so deciphering between voice, video, and data is simple. It is protocol agnostic, so it will function in circuit-switched or packet-switched networks.

MPP Multiplatform Phone; phone firmware that allows certain phone models to register to call control systems other than the CUCM. Phones registering to the CUCM use Enterprise firmware.

MRA Mobile and Remote Access; a Cisco feature that uses the Expressway series devices to proxy registrations to the CUCM from endpoints outside the corporate network without the use of a VPN.

MRGL Media Resource Group List; a prioritized list of Media Resource Groups.

MTLS Mutual TLS, also referred to as TLS Verify; a process in which both parties authenticate each other by verifying the provided digital certificate so that both parties are assured of the other’s identity.

MTP Media Termination Point; a media resource that allows the passing of a stream from one discontiguous connection to another.

multipoint An industrywide term used to describe any call that involves three or more participants.

multisite The option key available on CE software-based endpoints that enable the endpoints to host a multipoint call.

multiway Call escalation from a point-to-point call to a multipoint call hosted on a Multipoint Conferencing Unit. Multiway is a function used by the Cisco VCS through a setting called Conference Factory. It can be used only in conjunction with Cisco Telepresence MCUs, which are end-of-life products.

Mutual TLS See MTLS and TLS Verify.

MWI Message Waiting Indicator.

MX Multipurpose Experience; a branding type for Cisco Telepresence endpoints that offers a plug-and-play meeting room endpoint for customers that’s ready to use out of the box.

N

NANP North American Numbering Plan; a standardized national dial plan that assigns individual or blocks of telephone numbers, which are called E.164 addresses, to physical lines or circuits.

NAT Network Address Translation; a process of masquerading private IP addresses with public IP addresses.

network services Services that enable network-related capabilities in the CUCM and cannot be enabled or disabled by an administrator. However, they can be stopped, started, and restarted.

Newton The standard international unit for force. It is equal to the amount of net force required to accelerate a mass of one kilogram at a rate of one meter per second squared.

NR No Radio; a prefix signifying that all features that depend on a radio variant have been removed from certain Cisco phone models.

NRC rating Noise Reduction Coefficient rating; a measurement that informs the degree a substance absorbs sound energy, usually applied to building materials.

NTE Named Telephony Events; a method of sending DTMF from one endpoint to another after the call media has been established. The tones are sent as packet data using the already-established RTP stream and are distinguished from the audio by the RTP payload type field.

NTP Network Time Protocol; a protocol for synchronizing computer system clocks over IP networks. NTP has a hierarchical organization that is based on clock strata. Stratum 0 is an extremely precise clock source, such as an atomic clock or radio clock. A stratum 1 server is directly connected to a stratum 0 clock and can provide time information to other (stratum 2) devices, which in turn serve stratum 3 devices.

O

OAM Operation, administration, and maintenance; the processes that allow the Ethernet interfaces on devices to support the IEEE 802.3ah standard for operation, administration, and maintenance of Ethernet in access networks. The standard defines OAM link fault management.

OBTP One-Button-to-Push; a Cisco technology that allows participants to press a single button to join a scheduled meeting.

offline IM Instant messages stored for users who are currently offline.

off-net A setting that applies a marker to calls on the CUCM that leave the IP network and traverse the PSTN circuit-switched network. Applying this marker allows other call behavior settings to be applied.

omnidirectional mic A microphone with a polar pickup area intended to be at the center of a group of audio sources with a 360-degree pickup area.

on-net A setting that applies a marker to calls on the CUCM that remain on the IP network, even when they leave the corporate network. Applying this marker allows other call behavior settings to be applied.

Option 66 An industrywide protocol created by the IETF that allows TFTP server address information to be discovered during DHCP negotiation.

Option 150 A Cisco proprietary protocol that allows TFTP server address information to be discovered during DHCP negotiation.

OS Operating system.

OSD Onscreen display.

OSPF Open Shortest Path First; a Layer 3 routing protocol that uses a link-state routing algorithm and falls into the group of Interior Gateway Protocols, operating within a single autonomous system.

OU Organizational unit; a subcategory in an LDAP hierarchical tree used to categorize users or devices within an organization.

OV certificates Organization validation certificates; certificates for which the CA checks the right of the applicant to use a specific domain name and conducts some vetting of the organization. Additional vetted company information is displayed to customers when clicking on the Secure Site Seal, giving enhanced visibility in who is behind the site and associated enhanced trust.

overlap sending and receiving A function that allows digits to be sent or received one by one over an ISDN PRI.

over-sampling Sampling an analog input signal at a rate much higher than the minimum frequency required by the Nyquist-Shannon theorem.

P

packet loss The dropping of packets by the router due to congestion on a link.

partition A group of dialable patterns within the CUCM that share identical accessibility.

Pascal A measurement of one newton of pressure per square meter.

PAT Port Address Translation; an alternative to NAT but works in a similar fashion.

PBX Private branch exchange; a system that operates in a similar fashion to the automatic telephone exchange, except that the purpose of a PBX is to route calls within a business exclusively. PBXs can also connect to the outside world over the public telephone network, but they operate on the same circuit-switched network using POTS or ISDN.

PCM Pulse-code modulation; a technique in which the amplitude of an analog signal is converted to a binary value represented as a series of pulses.

PD Powered device; an IEEE term used to describe a device that receives power from another device using PoE.

PDL Plasma display panel; a type of flat-panel display that uses small cells containing plasma, which is ionized gas that responds to electric fields.

People+Content A proprietary protocol for content sharing that was originally designed by PictureTel and later developed by Polycom.

Perfmon counters Performance counters on RTMT that contain information on the CUCM, CUC, and IMP systems, as well as devices on these systems.

Phantom A location that specifies unlimited bandwidth for audio, video, and immersive calls. You specify this location to allow successful call admission control for calls across intercluster trunks that use the H.323 or SIP trunks to certain destinations that support the earlier location CAC feature.

PHB Per hop behavior; a Layer 3 QoS classification for marking packets.

PIMG PBX IP Media Gateway; a Cisco device used to integrate Cisco Unity Connection with the circuit-switched network.

PIP Picture-in-picture; a video screen layout in which a smaller video pane can exist within a larger video pane.

pixel A contraction of the words picture and element; it generally is used to describe the smallest component of a digital image.

pixel saturation The total number of pixels that make up a frame. Multiplying the two numbers in a resolution will provide the pixel saturation.

PKI Public key infrastructure; a set of roles, policies, and procedures needed to create, manage, distribute, use, store, and revoke digital certificates and manage public-key encryption.

PMP Personal Multiparty Plus; a product for which licenses can be purchased as Basic or Advanced. PMP Basic provides one PMP license per user that will support host meetings on the Cisco Meeting Server for up to four participants in each meeting. PMP Advanced provides one PMP license per user that will support host meetings on the Cisco Meeting Server for an undefined number of participants in each meeting. The number of participants for PMP Advanced licenses is limited only by the infrastructure that has been installed.

PoE Power over Ethernet; any of several standard or ad hoc systems that pass electric power along with data on twisted-pair Ethernet cabling. This allows a single cable to provide both data connection and electric power to devices such as wireless access points, IP cameras, and VoIP phones.

PoE Power Budget The total power a switch can supply down Ethernet cables.

polar pattern The directionality pattern of highest sensitivity for the microphone element.

policing Conditioning traffic before transmitting or receiving it through the network. Policingcontrols traffic bursts by marking or dropping packets when predefined limits are reached. Policing mechanisms can drop traffic classes that have lower QoS priority markings. Policing tools include class-based policing and committed access rate (CAR).

POTS Plain old telephone service; the means of audible communication using analog signals transmitted over wire.

Power Save A power-saving mode on Cisco IP phones where the backlight or screen turns off when the phone is inactive for a set interval. The backlight can be managed.

Power Save Plus A power-saving mode on Cisco IP phones where the phone screen turns on and off at times that are based on the employee’s work schedule. If work hours or work days change, an administrator can reconfigure that employee’s phone.

PQ Priority queue; a congestion management technique that guarantees strict priority in that it ensures one type of traffic will be sent, possibly at the expense of all others. For PQ, a low priority queue can be detrimentally affected, and, in the worst case, never allowed to send its packets if a limited amount of bandwidth is available or if the transmission rate of critical traffic is high.

Precision Camera A PTZ camera designed by Cisco but loosely based on the PrecisionHD camera. There are two models in this camera line. The Precision 40 camera supports an 8x zoom with an optical zoom of 4x. The Precision 60 supports up to 20x zoom capability.

Precision MIC 20 An omnidirectional Cisco tabletop microphone that uses a mini-jack and comes with a built-in mute button.

PrecisionHD Camera A PTZ camera originally designed by Tandberg, which was later acquired by Cisco. These cameras come in 4x, 8x, or 12x zoom capabilities.

prediction blocks Multiple variable-sized partitions into which a macroblock can be split. In an interpredicted macroblock, a separate motion vector is specified for each partition.

prefix A feature of H.323 dial plan architecture that allows easy access to services such as MCUs and gateways.

presence An indicator light that identifies if a user is online, offline, away, or busy.

Prestandard PoE A Cisco proprietary protocol that supplies power to IP phones over an Ethernet cable. Prestandard PoE supports up to 7W of power.

PRI Primary Rate Interface; a telecommunications interface standard used on an Integrated Services Digital Network (ISDN) to carry multiple DS0 voice and data transmissions between the network and a user. PRI is the standard for providing telecommunication services to enterprises and offices.

progressive scanning A scanning process by which pixels are populated within a frame working from top to bottom, left to right, and all lines are populated for each frame.

PSE Power sourcing equipment; an IEEE term used to describe any device capable of supplying power to another device using PoE.

PSTN Public switched telephone network; the world’s collection of interconnected circuit-switched public telephone networks.

PSTN routing A type of call routing that occurs between a site and the PSTN.

PTR Reverse Pointer Record; a setting that maps an IP address to a domain name, while a record maps the domain name to an IP address.

PTZ Pan, Tilt, Zoom; a description used for cameras that have the automated capability to be repositioned within a room.

PVC Permanent virtual circuit.

Q–R

Q.931 A standard based on the ISDN H.320 standard; it contains the source and destination IP address, in hexadecimal format, and any crypto-hash token if a call is to be encrypted. Q.931 is also responsible for the Alerting and Connect messages sent from the destination endpoint.

QoS Quality of service; a Layer 3 management tool used to allow or drop packets traversing through a router based on priority.

quantization The act of sampling an analog signal for the purpose of reducing it to a smaller set of manageable digital values. Also known as quantizing.

quantization error The difference between the resulting digital representation of an original analog signal and the actual value of the original analog signal.

RAS Registration, Admission, and Status; an ITU-created communication protocol that identifies all messaging schemes between any device and a gatekeeper using H.323.

RBG Red, Blue, Green; a component signal that breaks out a separate channel for luminance (Y), chrominance red (R), chrominance blue (B), and chrominance green (G).

RCA An analog audio and video cable for composite analog video. The name was taken from the company called Radio Corporation of America.

reflection An effect caused when an object of obstruction causes sound waves to bounce, or reflect, into another direction. The law of reflection is the angle of incidence equals the angle of reflection.

regions Sites where the bandwidth of audio and video calls can be set on a per-call basis. The audio limit on a region can result in filtering out codecs with higher bit rates. However, for video calls, the video limit constrains the quality (resolution and transmission rate) of the video. Regions control per-call bandwidth within a site and between sites.

remote browse A feature on RTMT that allows administrators to view traces on the server without downloading the trace files. Remote Browse can also be used to download these trace files.

rendezvous conferencing An always-on conference space that can be joined at any time.

resolution The number of pixels within a digital frame.

Restore Wizard A tool embedded in the backup and restore system. It is used if a recovery from a server failure is needed.

reverb time The amount of time a sound takes to eventually lose enough energy and drop below the level of perception.

reverberations The prolonging of a sound caused by the reception of multiple reflections off walls and ceilings within a few milliseconds of each other, also known as late reflections.

RF Radio frequency; In general terms, RF is any electromagnetic wave frequency that oscillates in the range of 3 kHz and 300 GHz. The Wi-Fi channel coverage provided by AP radios operatesin the 2.4 GHz and 5 GHz frequency bands.

RFC Request for Comments; a type of publication from the IETF that describes methods, behaviors, research, or innovations applicable to the working of the Internet and Internet-connectedsystems.

RGBQuantizationRange A video output setting on Cisco CE software-based endpoints. Devices connected to an HDMI output should follow the rules for RGB video quantization range defined in CEA-861. Unfortunately, some devices do not follow the standard and this configuration on CE endpoints may be used to override the settings to get a perfect image with any display. Most HDMI displays expect full quantization range.

RIP Request In Progress; a RAS message sent by a gatekeeper that informs the H.323 endpoint that a request is being processed.

RIS Real-Time Information server; a server that maintains real-time information such as device registration status, performance counter statistics, critical alarms generated, and so on. The Cisco RIS Data Collector service provides an interface for applications, such as the IM and Presence Real-Time Monitoring Tool (RTMT), SOAP applications, and so on, to retrieve the information that is stored in all RIS nodes in the cluster.

RMS Root mean squared; a method used to calculate a comparable measure of power efficiency.

RMS Rich Media Session; a type of license that can be installed on the Expressway Core and Expressway Edge servers. These licenses allow for B2B calling and SIP-to-Microsoft interworking capabilities.

RNAR Ring No Answer Revision; a ring duration timer used with hunting on the CUCM. When a device rings to the full duration of the RNAR, the hunt will continue on to the next participant.

root CA The certificate authority server that generates, signs, and authenticates certificates used for authentication. This is the authority for all certificates signed by it.

root CA certificate A certificate that establishes a trusted chain beginning at the root CA, through the root CA certificate, and ending at the certificate that was signed.

route filter A filter that restricts certain numbers that are otherwise allowed by the route pattern.

route group Available paths; the route group distributes calls to gateways and trunks.

route list A prioritized list of the available paths for a call.

route pattern A pattern that matches an external dialed string and uses it to select a gateway or a corresponding route list.

routing prefix A type of prefix that is configured on a gateway or bridge and registers to an H.323 gatekeeper. It is used to route all calls to that server regardless of the following digits.

RRQ Registration Request; a RAS message initiated by an endpoint to attempt to register to a gatekeeper. The gatekeeper will respond with either RCF (Registration Confirm) or RRJ (Registration Reject).

RSA Rivest-Shamir-Adleman; a public-key cryptographic system used for secure data transmission.

RTMT Real-Time Monitoring Tool; a service that runs as a client application and uses HTTPS and TCP to monitor system performance, device status, device discovery, CTI applications, and voice-messaging ports.

RTP Real-time Transport Protocol; a protocol used over UDP to carry real-time media traffic.

S

sample Measurement of an analog signal that must be taken at precise points.

SBC Session Border Controller; an element that serves as a demarcation point between the enterprise and the service provider IP networks.

SCCP Skinny Call Control Protocol; a Cisco proprietary protocol used for voice communication over IP.

Scheduler A Disaster Recovery tool in the CUCM that allows the administrator to perform automatic backups in specific time frames.

SDP Session Description Protocol; a protocol used during SIP call setup to exchange capabilities and identify UDP ports to be used.

self-provisioning A feature that allows phones to be provisioned across the network by enabling end users to provision their own phones without contacting an administrator.

Server Report A Cisco Unified Serviceability Report generated on the CUC that contains statistics on the server performance for the day.

service A set of parameters that encapsulate a specific feature or function within the Cisco Unified Communications Manager.

service parameter A factor used to define settings for a specific feature service on an individual server. Unlike enterprise parameters, service parameters are defined separately for each server in the cluster and for each feature service enabled on each server.

servlet A Java class that receives an HTTP or HTTPS request and generates a response that is based on that request.

shadow A system location created for inter-cluster Enhanced Location CAC. To pass locations across clusters, the SIP inter-cluster trunk (ICT) must be assigned to the system location Shadow.

shaping mechanisms Mechanisms used on output interfaces to help smooth out mismatches in the network and limit transmission rates. Although these mechanisms are typically used to limit the flow from a high-speed link to a low-speed link, shaping could also be used to manage the flow of traffic at a point in the network where multiple flows are aggregated.

shotgun mic A directional mic with a narrow pickup range, but it can also pick up sound from the greatest distances.

SIF Source input format; a format defined by the ISO as part of MPEG-1. Often referred to as a “Constrained parameters bit stream,”SIF defines the minimum specifications any decoder should be able to handle to provide a decent balance between quality and transmission performance.

SIMPLE Session Initiation Protocol for Instant Messaging and Presence Leveraging Extensions; an instant messaging and presence protocol suite based on Session Initiation Protocol.

sine wave A mathematical curve indicating that all the signal energy is concentrated at one frequency.

SIP Session Initiation Protocol; an IETF signaling protocol used for real-time sessions, such as voice, video, and instant messaging.

SIP proxy A function of the SIP server used to connect devices in voice or video calls.

SIP registrar A function of the SIP server used to map SIP URI addresses to IP addresses for SIP endpoints when they register.

SIP server The call control device for SIP voice and video systems.

SIPS A term used to define a secure layer over SIP; Secure SIP, or Secure Session Initiation Protocol.

SLDAP Secure Lightweight Directory Access Protocol; a protocol that enables LDAP to be sent over a Secure Sockets Layer connection and can be enabled by adding the LDAP server into the Tomcat trust store within the Unified CM Platform Administration.

SMP Shares Multiparty Plus; an application that allows licenses to be added to the Cisco Meeting Server so that any user can create and join a meeting using this license.

SNMP Simple Network Management Protocol; an Internet standard protocol for collecting and organizing information about managed devices on IP networks and for modifying that information to change device behavior.

SNR Single Number Reach.

SOAP Simple Object Access Protocol; a messaging protocol specification for exchanging structured information in the implementation of web services in computer networks. Its purpose is to provide extensibility, neutrality, and independence.

Softphone mode A user mode in which the Cisco Jabber client behaves like an IP phone and originates and terminates all audio and video communication interactions on the software endpoint itself.

sound pressure The disruption of the normal atmospheric pressure caused by a sound wave. Half of a sound wave is made up of the compression of the medium, and the other half is the decompression or rarefaction of the medium. Sound pressure is measured in pascals or millibars.

Speaker Track 60 A dual-camera system that enhances the user experience by each camera zooming in on an individual participant in a meeting based on who’s speaking. If one camera is zoomed in on one participant in a room and another participant starts speaking, the second camera will zoom in on that participant before the camera switches to the new participant view.

SPID Service profile identifier.

SRST Survivable Remote Site Telephony; a redundancy feature available on Cisco IOS routers that allows Cisco Unified IP phones registered to the Cisco Unified Communications Manager from remote office locations to register to their local router during WAN network failure events.

SRTP Secure Real-time Transport Protocol; a secure protocol over TLS used over UDP to carry real-time media traffic.

SRV record A location service within DNS that can be used to identify protocols, port numbers, and host names of servers for particular services.

SSID Service Set Identifier; the name assigned to a wireless broadcast signal so that users can easily select the Wi-Fi network to which they need to connect.

SSL Secure Sockets Layer; a legacy cryptographic protocol that provides communications security over a computer network for TCP and UDP traffic. SSL has been replaced by the more secure TLS.

SSO Single sign-on; a form of identity management that allows users to sign into one application, such as a computer, and access all other associated applications.

stacker A link efficiency compression algorithm that compresses the payload of Layer 2 frames. Also referred to as a predictoralgorithm.

stereo An audio signal that has two channels, one for left speakers and one for right speakers.

STP Spanning Tree Protocol; a Layer 2 protocol that runs on switches and is specified by the IEEE standard 802.1d. The purpose of STP is to prevent loops when configuring redundant paths within the network. Different flavors of STP can be used, and each one requires different timing for convergence. Therefore, it is recommended that the same version of STP is used within a single environment. Some of the other Spanning Tree Protocols that exist include IEEE 802.1w Rapid Spanning Tree Protocol (RSTP) and IEEE 802.1s Multiple Instance Spanning Tree Protocol (MISTP).

stratum A hierarchical organization within NTP that is based on clock strata. Stratum 0 is an extremely precise clock source, such as an atomic clock or radio clock. A stratum 1 server is directly connected to a stratum 0 clock and can provide time information to other (stratum 2) devices, which in turn serve stratum 3 devices, and so on.

STUN Session Traversal Utilities for NAT; a set of methods that requires a STUN client, which could be a phone or some other device that sends packets to a STUN server on the Internet. The STUN server replies with information about the IP address and ports from which the packets were received and detects the type of NAT device through which the packets were sent. The STUN client can then use the public IP and assigned port in constructing its headers so that external contacts can reach the client without the need for any other device or technique. After the STUN server assigns a port, it is no longer involved in the line of communication.

supercardioid mic A directional mic that has a narrower range of focus. As a result of this narrowing, a small lobe develops behind the mic and may require consideration.

S-Video Separate video, or Y/C; a composite video for analog video signals. S-Video separates the luminance (Y) from the chrominance (C). Although S-Video offers better quality video than other composite video components, it cannot compare to the quality of video from component video.

SX Solutions Experience; a branding type for Cisco Telepresence endpoints that offers integrator options for customers.

symmetric cryptography A process of negotiating between a server and client that details which encryption algorithm and cryptographic keys to use before the first byte of data is transmitted. Identification is usually in the form of digital “certificates”that contain the server name, the trusted certificate authority, and the server’s public encryption key.

synchronization agreement A type of agreement that specifies a search base that is a position in the LDAP tree where the Cisco Unified Communications Manager will begin its search for user accounts to import.

T

T.150 An early ITU substandard of the H.320 umbrella standard that allows content sharing between devices; Terminal Equipment and Protocols for Telematic Services, otherwise known as the Telewriting Terminal Equipment.

T302 Timer A setting that specifies the interdigit timer for variable-length numbers. Reducing the default value will speed up dialing (shorter post-dial delay).

TC Telepresence Collaboration; legacy software that came preloaded on Cisco Telepresence endpoints. It has since been replaced by CE software.

TCP Transmission Control Protocol; a routing protocol that ensures communication by use of acknowledgments. If an acknowledgment is not received, the packet will be retransmitted.

TCP/IP Transmission Control Protocol over Internet Protocol; a standard used to control how information is transmitted and received over the Internet.

TDM Time-division multiplexing; a method of transmitting and receiving independent signals over a common signal path by means of synchronized switches at each end of the transmission line so that each signal appears on the line only a fraction of time in an alternating pattern.

TDoS Telephony denial of service; a security mechanism used to prevent attacks.

TEI Terminal endpoint identifier; a number between 0 and 127, where 0–63 are used for static TEI assignment, 64–126 are used for dynamic assignment, and 127 is used for group assignments. These numbers are used exclusively within an ISDN environment.

telepresence An industry term used to identify systems capable of high-quality video and audio communications.

text conferencing Ad hoc group chat or persistent group chat; it is supported as part of the Jabber XCP feature set.

TFTP Trivial File Transfer Protocol; a protocol that builds configuration files and serves embedded component executables, ringer files, and device configuration files.

TIMG T1 IP Media Gateway; a Cisco device used to integrate Cisco Unity Connection with the circuit-switched network.

TIP Telepresence Interoperability Protocol; an open standard that allows RTP and RTCP streams to be multiplexed together.

TLS Transport Layer Security; a secure layer of the TCP protocol that uses encryption to scramble data being shared between nodes.

TLS Verify A process in which both client and server present and authenticate each other by verifying each other’s provided digital certificate so that both parties are assured of the other’s identity. This process occurs before communication can be established. Also known as Mutual TLS.

TMS Telepresence Management Suite; a management solution for Cisco Collaboration that runs on a Microsoft Windows Server.

ToD Time of day; a routing component of call privileges that controls when routing is allowed to occur.

TON Type of number; a record sent with each telephony transaction through the PSTN. There are two components of a TON: the number type of a called number and the numbering plan. Basically, four different types of numbers can be used. They are Cisco CallManager, National, International, or Unknown, which is the default. Different plans can be used as well, such as Cisco CallManager, ISDN, National Standard, Private, or Unknown. Each type and plan can be used to determine when and how a translation rule should be applied.

ToS Type of service; a Layer 3 QoS classification for marking packets.

Touch 10 A 10-inch multitouch capacitive control pad that is used to control a Telepresence endpoint.

transcoding Converting the data stream from one compression type to another.

transform block A processing unit that serves as input to a linear block transform. In the YCbCr color space, each single 16×16 macroblock consists of 16×16 luma (Y) samples and 8×8 chroma (Cb and Cr) samples. These samples are split into four Y blocks, one Cb block, and one Cr block.

translation pattern A pattern that when matched provides an entry to the call-routing table. If a dialed number matches the pattern, another number, which is the translated number that is configured at the translation pattern, is looked up in the call-routing table.

TRAP Telephone Record and Playback.

traversal chaining A more secure means of traversing firewalls when one Expressway is placed within a DMZ. As well as acting as a traversal server, an Expressway-E can act as a traversal client to another Expressway-E. If you chain two Expressway-Es, the first Expressway-E is a traversal server for the Expressway-C. That first Expressway-E is also a traversal clientof the second Expressway-E. The second Expressway-E is a traversal server for the first Expressway-E.

traversal client zone The zone created on the traversal client, which is the Expressway Core in a typical Cisco Collaboration environment, used to establish communication with the traversal server. Some Cisco endpoints can also be traversal clients, as well as the Expressway Edge. Also, the legacy Cisco VCS Control and VCS Expressway can support the role of traversal client.

traversal server zone The zone created on the traversal server, which is the Expressway Edge in a typical Cisco Collaboration environment, used to proxy communication messages to the internal network through the traversal client. The legacy Cisco VCS Expressway can also support the role of traversal server.

traversal zone A zone that is used for communication through a firewall. An Expressway Core and an Expressway Edge are required to set up a traversal communication through a firewall. The Expressway Core needs to be located inside the firewall, whereas the Expressway Edge needs to be located outside the firewall or in a DMZ.

TRC Telepresence Remote Control.

TSPEC Traffic Specification; Cisco APs and wireless Unified Communications clients now use Traffic Specification instead of the QoS Basic Service Set for call admission control.

TTS Text-to-Speech.

TUI Telephone user interface; an interactive means of accessing the Cisco Unity Connection server using the DTMF touch tones on a telephone.

TURN Traversals Using Relays around NAT; a protocol that connects clients behind a NAT to a single peer. Its purpose is to provide the same protection as that created by symmetric NATs and firewalls. Symmetric NATs use dynamic ports that often change. Therefore, the TURN server acts as a relay so that any data received is forwarded on to the client, and port allocation can be updated on the fly. The client on the inside can also be on the receiving end, rather than the sending end, of a connection that is requested by a client on the outside.

TVS Trust Verification Service; a remote trust store on the CUCM that can be used by phones with limited storage so that a full certificate trust store does not have to be placed on each IP phone.

two-stage dialing A type of connectivity in which all endpoints share a single PSTN number.

U

UC Unified Communications; a set of products that provide a consistent unified user interface and experience across multiple devices and media types.

UCCE Unified Contact Center Enterprise; a service that helps companies deliver proactive and personalized customer experiences for contact centers with up to 24,000 agents. Fault tolerance helps ensure uninterrupted operation. Comprehensive reporting gives you the business intelligence needed to optimize your contact center’s performance.

UCCX Unified Contact Center Express; a complete “Contact Center in a Box.”It delivers call routing, management, and administration features, and is designed for businesses ranging from very small to enterprise branch offices with up to 400 agents.

UDP User Datagram Protocol; an alternative communications protocol to Transmission Control Protocol used primarily for establishing low-latency and loss-tolerating connections between applications on the Internet.

UltraHD Also called UHD or Ultra High-Definition. This resolution defines the latest 4K resolutions available at 3840×2160.

UN Unsolicited Notify; a DTMF relay method used primarily by Cisco IOS SIP gateways to transport DTMF digits using SIP NOTIFY messages. Unlike KPML, these NOTIFY messages are unsolicited, and there is no prior registration to receive these messages using a SIP SUBSCRIBE message. Also, unlike KPML, which has an XML-encoded body, the message body in these NOTIFY messages has a 10-character encoded digit, volume, and duration, describing the DTMF event. Similar to KPML, UN messages are OOB.

unbalanced audio cable A type of cable that has two wires: one to carry the positive (+) side of a signal, and the other wire shares both the negative (−) side of the signal and the grounding shield. Inside the cable itself, the signal wire is typically in the center of the cable with the ground wire surrounding it. The ground wire serves two functions. It carries part of the audio signal and serves to shield the main signal wire to some degree from outside interference from noise. It does help reject some noise, but the wire itself also acts like an antenna and picks up noise.

under-sampling Sampling an analog input signal at a rate much lower than the minimum frequency required by the Nyquist-Shannon theorem.

Unified Communications Traversal Zone A special type of traversal zone on Expressway servers that are used for MRA deployments. This type of traversal zone requires that TLS Verify be used for the highest security in communications.

Unified CVP Unified Customer Voice Portal; a system that combines open-standards support for speech with intelligent application development and industry-leading call control to deliver personalized self-service to callers.

UPN User Principal Name; the name of a system user in an email address format. The username is followed by the at sign (@) followed by the name of the Internet domain with which the user is associated.

URI Uniform Resource Identifier; a string of characters that identifies a particular resource. URIs typically take the form of User@FQDN.

URL Uniform Resource Locator; a reference to a web resource that specifies its location on a computer network and a mechanism for retrieving it. URLs typically take the form of User.FQDN.

USB Universal Serial Bus; an industry standard that establishes specifications for cables and connectors and protocols for connection, communication, and power supply between computers, peripheral devices, and other computers.

V

VCS Video Communications Server; a Cisco (formerly Tandberg) call control device designed specifically for video Telepresence endpoints and devices. The base code of the Cisco VCS is used with the Cisco Expressway servers as well.

VGA Video graphics array; a graphics standard for an analog composite video display controller. The cable that connects to the VGA controller is called a VGA connector.

VISCA A professional camera control protocol that was originally designed by Sony. This protocol provides pan, tilt, and zoom capabilities to the camera from a remote.

visible spectrum A small area of the EMR spectrum that is perceivable to the human eye in the form of color.

VLAN Virtual local-area network; virtual partitions at Layer 2 of the network used to decouple traffic and logically group data packets being sent across the network. VLANs can be used for QoS.

VNC Virtual network computing; a graphical desktop-sharing system that uses the Remote Frame Buffer protocol to remotely control another computer. It transmits the keyboard and mouse events from one computer to another, relaying the graphical-screen updates back in the other direction, over a network.

Voice VLAN The virtual partition in the Layer 2 part of the network allocated specifically for voice and video network traffic.

voicemail port An entity that requests a call that the Cisco Unified Communications Manager is routing. When a call is sent to a voicemail system, that system can request that the call be transferred to another directory number, to a PSTN destination, such as the cell phone of a user, or to an assistant.

VoIP Voice over IP; an audio technology that allows voice communication to be translated into a binary format and encapsulated into packets and sent across an IP network.

VPN Virtual private network; a protocol used to connect two autonomous networks across a WAN.

VRRP Virtual Router Redundancy Protocol; an IETF protocol based on RFC 5798 that offers default gateway redundancy similar to HSRP. However, these two protocols are mutually exclusive and cannot operate in tandem with one another.

VSS Virtual Switching System; a method that ensures redundancy on Cisco Catalyst switches.

VUI Voice user interface; an interactive means of accessing the Cisco Unity Connection server using audio prompts and communication.

VVID Voice VLAN ID; the numeric value associated with the voice VLAN.

W

WAN Wide-area network; a telecommunications network that extends over a large geographical area for the primary purpose of computer networking.

WAP Wireless access point; the wireless router that wireless devices connect to.

watt The rate of transfer of energy in one second, or one joule per second. A joule is equal to the energy expended in applying a force of one newton through a distance of one meter.

wavelength The distance to complete one cycle in an audio wave.

WebDAV Web Distributed Authoring and Versioning; an extension of the Hypertext Transfer Protocol that allows clients to perform remote web content authoring operations. WebDAV is defined in RFC 4918 by a working group of the Internet Engineering Task Force.

Webex endpoints Cisco Telepresence endpoint products based on the CE endpoint software that offer both integrator solutions and plug-and-play options ready to use out of the box.

Webex Meeting App A meeting application that allows users to join or start Webex meetings. This app can also be used to share content during a meeting hosted in the Webex cloud.

Webex Teams app A messaging application that allows users to share content and instant messages with other users point-to-point or as a group in a Teams Space. The app can also be used to join Webex meetings or share content during a meeting hosted in the Webex cloud.

WebRTC A free, open project that provides browsers and mobile applications with Real-Time Communications capabilities via simple APIs.

WebSocket A bidirectional persistent connection between a client and a server where information can flow back and forth without the overhead of initiating a new TCP connection or authentication for every request.

WFQ Weighted Fair Queuing; an algorithm that does not require configuration of access lists to determine the preferred traffic on a serial interface. Rather, the fair queue algorithm dynamically sorts traffic into messages that are part of a conversation.

white balance A setting used in cameras to set the reference value for white so that color anomalies caused by color temperature can be corrected.

WLAN Wireless local-area network, also known as Wi-Fi. Instituted, monitored, and managed by the IEEE, WLAN standards include 802.11a/b/g/n/ac and 802.11ax, also known as Wireless 6.

WLC Wireless LAN Controller; a device used to manage wireless access points.

WMM TSPEC Wi-Fi Multimedia Traffic Specification; the QoS mechanism that enables WLAN clients to provide an indication of their bandwidth and QoS requirements so that APs can react to those requirements.

WRED Weighted Random Early Detection; an early detection congestion avoidance mechanism that ensures high-precedence traffic has lower loss rates than other traffic during times of congestion.

X–Y–Z

xAPI Experience API; a new specification for learning technology that makes it possible to collect data about the wide range of experiences a person has (online and offline). This API captures data in a consistent format about a person or group’s activities from many technologies. Very different systems are able to securely communicate by capturing and sharing this stream of activities using xAPI’s simple vocabulary.

XCP Extensible Communications Platform; a highly programmable presence and messaging platform that supports the exchange of information between applications in real time.

XML application A tool that lets you create interactive service applications with XML objects that are defined for Cisco Unified IP Phones.

XMPP Extensible Messaging and Presence Protocol; a set of open technologies for instant messaging, presence, multiparty chat, voice and video calls, collaboration, lightweight middleware, content syndication, and generalized routing of XML data.

YCbCr A color representation model used with digital video signals. Y is the luminance signal, Cb is the chroma blue signal, and Cr is the chroma red signal. Green is deduced from the three signals using an algorithm.

YPrPb A color representation model used with analog signals. Y is the luminance signal, Pr is the primary red signal, and Pb is the primary blue signal. Green is deduced from the three signals using an algorithm.

YUV A component video process, where Y represents the luminance component, and UV represents the chrominance components. The term is used for a specific analog encoding of color information in television systems.

Zoom The adjustability of a lens that creates the illusion of bringing objects closer, or increasing magnification.