INDEX
A
A (address) DNS records, 339
AAA (Authentication, Authorization, and Accounting).
multilayer switches, 420–421
overview, 375–377
absorption issues in Wi-Fi, 533
abstraction in virtualization, 545–547
acceptable use policies (AUPs)
provisions, 630–631
Wi-Fi, 534
access
acceptable use policies, 630–631
administrative, 671–672
data centers, 584
hardware, 681
network policies, 631–632
switches, 397–398
telecommunications room location, 136
access control lists (ACLs)
administrative access, 671–672
authorization models, 372
MAC filtering, 504
router issues, 769–770
access control vestibules, 682
access-list command for firewalls, 700
access tokens in Kerberos, 379
accounting in AAA, 377
accounts
cloud computing, 569–570
controlling, 685–688
malicious, 670–671
trusted and untrusted, 669–670
user, 685–688
ACK (Acknowledgment) messages
DCF, 493
DHCP, 216
three-way handshakes, 175, 283
acknowledgment number field in TCP, 175
ACLs. See access control lists (ACLs)
Acrylic Wi-Fi, 511
actions for troubleshooting, documenting, 756
activation of viruses, 673
active-active aggregation connections, 766
active-active high availability, 591
Active Directory
DDNS, 343
DNS servers, 333–334
Kerberos authentication, 378–379
LDAP, 391
RADIUS, 501
state data, 646
active FTP, 306
active-passive high availability, 592, 766
activity lights for NICs, 161
actors, threat, 640
actuators
DCS, 620
edge access control, 688–689
SCADA, 624
ad hoc mode in 802.11, 488
ad hoc networks, setting up, 514–515
adapters, loopback, 163
Adaptive Security Appliance (ASA), 699, 771
address (A) DNS records, 339
Address Resolution Protocol (ARP)
arp utility, 741
cache poisoning, 662–666
requests, 179–180
spoofing, 660
TCP/IP, 195–196
addresses
IP. See IP addresses
MAC. See media access control (MAC) addresses
administrative access control, 671–672
administrative distance, 262–263
ADSL (asymmetric DSL), 456
advanced distance vector protocols, 262
Advanced Encryption Standard (AES), 358
advanced networking devices, 410
adware, 674
AES (Advanced Encryption Standard), 358
African Network Information Centre (AFRINIC), 430
agents
network security, 690–691
VLANs, 408
aggregation
IPv6, 438–441
multilayer switches, 414
NICs, 160
route, 259
troubleshooting, 765–766
aggregation layers in data centers, 585
AH (Authentication Header) protocol, 387
Aircrack-ng tool, 643
airflow in environment, 593
AirMagnet Survey Pro tool, 509–511
AirPort Utility, 529–530
alerts
cloud, 570
emergency systems, 594
interface errors, 719
SNMP, 712
alignment of antennas, 519
Amazon Echo products, 608–609
American National Standards Institute (ANSI), 451
American Registry for Internet Numbers (ARIN), 197, 430
amplification in denial of service, 667
angled physical contact (APC) connectors, 99
Angry IP Scanner, 747–748
ANSI (American National Standards Institute), 451
ANSI/TIA-606-C naming convention, 124
Ansible tool, 566–568
antennas
infrastructure networks, 515–520
omnidirectional, 516–518
patch, 518–519
placement, 515–516
polarization and alignment, 519–520
satellites, 461
unidirectional, 518
anti-malware programs
overview, 696–697
rogue, 694
anycast addresses, 432
AnyConnect DTLS VPN, 476
APC (angled physical contact) connectors, 99
APIPA (Automatic Private IP Addressing), 223–224
APIs (Application Programming Interfaces), 34
APNIC (Asia-Pacific Network Information Centre), 430
appliance problems, 771
application-aware firewalls, 698
Application layer
OSI seven-layer model, 33–35
TCP/IP protocols, 176–177
application planes in SDN, 563
Application Programming Interfaces (APIs), 34
applications, TCP/IP. See TCP/IP applications
approval process in change management, 635
areas, OSPF, 261
ARIN (American Registry for Internet Numbers), 197, 430
ARP. See Address Resolution Protocol (ARP)
arp utility, 741
ARPANET, 320
arping utility, 741–742
ASA (Adaptive Security Appliance), 699, 771
Asia-Pacific Network Information Centre (APNIC), 430
ASNs (Autonomous System Numbers), 258
ASs (Authentication Servers) in Kerberos, 379
ASs (Autonomous Systems), 258–259
assessing data centers, 600–602
assets
disposal, 672
monitoring, 684
risk assessment, 640
tags, 683
assigning
IP addresses, 197–198, 209–210
asymmetric DSL (ADSL), 456
asymmetric-key encryption, 358–360
asymmetric routing, troubleshooting, 771
attacks
network security. See network security
WPS, 497
attenuation
copper cabling, 153
optical link budget, 768–769
Wi-Fi, 533
attributes, authentication, 371
audits
data centers, 601–602
logs, 725
AUPs (acceptable use policies)
provisions, 630–631
Wi-Fi, 534
authentication
AAA, 377
with encryption, 385–387
remote access, 467
secure applications, 310
user standards, 373–380
Authentication, Authorization, and Accounting (AAA).
multilayer switches, 420–421
overview, 375–377
Authentication Header (AH) protocol, 387
Authentication Servers (ASs) in Kerberos, 379
authoritative name servers, 322, 326
authorization
AAA, 377
remote access, 467
auto-medium-dependent interface crossover (MDI-X), 84
Automatic Private IP Addressing (APIPA), 223–224
automation
home, 607–609
IaC, 554–555
virtualization, 566–567
Autonomous System Numbers (ASNs), 258
Autonomous Systems (ASs), 258–259
availability in CIA triad, 657
available leases in DHCP, 216
B
backbones
data centers, 585
Gigabit Ethernet, 105–106
OSPF areas, 261
backdoor access, 688
backhaul connections in SD-WAN, 455
backoff in CSMA/CA, 492
backups
anti-malware programs, 696
business continuity, 647–648
configuration, 637
data centers, 587
disaster recovery, 646–647
high availability, 592
patches, 637
router setup, 273
in troubleshooting, 750
bad ports in NICs, 163
badges, 682
bandwidth
802.11, 491–492
cable category ratings, 56–57
channel, 491
dynamic routing, 252
Ethernet, 81
full-duplex, 96
link aggregation, 765–766
OSPF, 261
QoS, 413–414
VTC, 617
WAPs, 532–533
bandwidth-efficient encoding schemes, 57
bandwidth shaping in multilayer switches, 413–414
bandwidth speed testers, 748
banner grabbing, 670
bare-metal data centers, 589
barrel connectors, 53–54
baseband
10BASE-FL, 77
100BASE-FX, 95
100BASE-T, 92
baselines
data center configurations, 600
performance, 721
troubleshooting, 760
basic service set identifiers (BSSIDs), 490–491
basic service sets (BSSs) in 802.11, 489
BC (business continuity), 647–648
BCPs (business continuity plans), 647–648
beacons in infrastructure networks, 521–522
beam antennas, 518
beamforming in 802.11n, 495
bend radius limitations in fiber-optic cabling, 155
BGP (Border Gateway Protocol), 257–260
bidirectional (BiDi) transceivers, 104–105
bidirectional wavelength division multiplexing (BWDM), 451–452
binary and decimal values, converting, 182–183, 207–209
binary encryption, 356–357
biometrics, 371
bitwise operations in encryption, 357
BIX blocks, 126
blacklists, 504
BLE (Bluetooth Low Energy) technology, 612
block ciphers, 358
blocked ports, 769
blocked services, 678
blocking policies, 772
blocks
data centers, 587
network, 197
Bluetooth, 611–612
Bluetooth Low Energy (BLE) technology, 612
BNC connectors, 51–52
bonding
NICs, 160
port, 414
Border Gateway Protocol (BGP), 257–260
botnets, 667
bots, 667
bottlenecks, monitoring, 725
Bottom of Label Stack in MPLS headers, 453
bottom-to-top OSI model troubleshooting approach, 753
bounce in Wi-Fi, 533
BPDU guards, 86
BPDUs (bridge protocol data units), 85–86
branch offices for data centers, 589
breaches, data, 630
bridge protocol data units (BPDUs), 85–86
bridges
DSL, 458
Ethernet, 81
wireless networks, 527
bridging loops, troubleshooting, 767
bring your own device (BYOD) deployment, 632–633
broadband
10BASE-T, 72
vs. baseband, 92
cable, 459–461
broadcast addresses, 16
broadcast domains in switches, 83
broadcast storms, troubleshooting, 766–767
broadcasts
MAC addresses, 16
packets, 198
routing tables, 241–242
broken cable, 733
browsers, HTTP and HTTPS for, 307–311
brute force attacks
Caesar cipher, 355–356
passwords, 669
BSSIDs (basic service set identifiers), 490–491
BSSs (basic service sets) in 802.11, 489
buffers for fiber-optic cabling, 59
bus topologies
Ethernet, 71–72
overview, 44–46
business continuity (BC), 647–648
business continuity plans (BCPs), 647–648
business risk assessments, 644–645
BWDM (bidirectional wavelength division multiplexing), 451–452
BYOD (bring your own device) deployment, 632–633
C
C2 (command and control) protocols, 667
cable drops, 135
cable strippers, 736
cable testers, 733–734
cable trays, 137–138
cabling and connectors, 50
broadband, 459–460
coaxial, 50–54
copper, 50–59
fiber-optic, 59–62
fire ratings, 63
IEEE standards, 63–64
overview, 43
Physical layer, 6
review, 65–66
structured. See structured cabling
toners, 166–168
troubleshooting, 761
twinaxial, 54
twisted pair, 54–59
cache poisoning
ARP, 662–666
DNS, 660
caches
ARP, 180
flow monitoring, 716
Cacti application, 723–725
Caesar cipher, 355–356
cameras, 685
campus area networks (CANs), 449, 605–607
canonical name (CNAME) DNS records, 339–340
capacitance of coaxial cable, 53
captive portals in Wi-Fi, 534
capture files with packet sniffers, 713
capture filters in protocol analyzers, 715
carrier-sense multiple access with collision avoidance (CSMA/CA), 492–493
carrier-sense multiple access with collision detection (CSMA/CD), 79–81, 492–493
CAs (certificate authorities), 368–370
category (Cat) cable ratings, 56–58
CCE (Certified Computer Examiner), 648
CCMP (Counter Mode Cipher Block Chaining Message Authentication Code Protocol), 502
CCMP-AES cipher, 502
CCTVs (closed-circuit televisions), 685
CDMA (code-division multiple access), 463
CDNs (content delivery networks), 432
cellular access, 461–462
5G, 465
GSM and EDGE, 462–463
HSPA+, 464
LTE, 464–465
CENELEC, 113
central boxes
description, 7
frames, 15–16
Cerf, Vinton, 23
certificate authorities (CAs), 368–370
certificates
HTTPS, 387–388
nonrepudiation, 366–370
SSL, 385
troubleshooting, 771
Certified Computer Examiner (CCE), 648
Certified Forensic Computer Examiner (CFCE), 648
chain of custody, 650
Challenge Handshake Authentication Protocol (CHAP), 374
change
managing, 634–636
in troubleshooting, 751–752
change requests, 635
channels
802.11, 491–492
802.11g, 495
infrastructure networks, 524–525
overlap issues, 528–529
unencrypted, 679
Wi-Fi issues, 528–529
CHAP (Challenge Handshake Authentication Protocol), 374
chassis sensors, 718
checksums
hashes, 361
TCP, 175
choose your own device (CYOD), 633
CI/CD (continuous integration/continuous deployment), 555
CIA (confidentiality, integrity, and availability) triad, 656–657
CIDR. See Classless Inter-Domain Routing (CIDR)
cipher locks, 683
ciphers and ciphertext, 355
Cisco Configuration Professional, 269
Cisco IOS, 265–267
Cisco Network Assistant, 269
Cisco Prime Infrastructure, 269
cladding for fiber-optic cabling, 59
class of service (CoS) in DSCP, 617–618
classes for IP addresses, 197–199
classless addresses, 207
Classless Inter-Domain Routing (CIDR)
host calculations, 201
subnet masks, 196
subnets, 199–209
summary, 209
cleartext credentials, 679–680
cleartext data, 355
client-server networks, 38
client-to-site VPN connections, 475
clientless VPNs, 475
clients
DHCP, 214–216
disassociation issues, 537
DNS, troubleshooting, 343–347
e-mail, 302–303
infrastructure networks, 526
troubleshooting, 764
WAPs, 508
Wi-Fi installation, 513–514
Wi-Fi isolation, 504–505
CLIs (command-line interfaces), 739
clock strata in NTP, 286
close-ended questions in troubleshooting, 751
closed-circuit televisions (CCTVs), 685
cloud-based anti-malware, 697
cloud bursting, 553
cloud computing
DaaS, 574–576
deployment methods, 553
IaC, 554–556
overview, 548–549
PaaS, 551–552
resource interconnections, 576–578
resource management, 569–570
review, 578–580
Rocket.Chat platform, 564–568
SaaS, 552–553
service-layer cake, 549
virtualization. See virtualization
cloud sites, 647
clusters
load balancing, 591
multilayer switches, 411
CNAME (canonical name) DNS records, 339–340
co-resident switches, 584
coarse wavelength division multiplexing (CWDM), 452
coaxial cable, 50–54
COBO (corporate-owned, business only) deployment model, 633
code-division multiple access (CDMA), 463
cold sites, 647
collisions
CSMA/CA, 492–493
CSMA/CD, 79–81
troubleshooting, 768
colons (:) in IPv6 addresses, 427–428
Combs, Gerald, 713
command and control (C2) protocols, 667
command-line interfaces (CLIs), 739
common agreements, 639–640
common polarization in antennas, 519
Common Vulnerabilities and Exposures (CVE) database, 659
communications technologies for Internet of Things, 610–612
community clouds, 553
company security policies, troubleshooting, 772
complexity of passwords, 638
component relocation in virtualization, 548
compromised system symptoms, 695
computer telephony integration (CTI), 614
concentrators for VPNs, 474
confidentiality, integrity, and availability (CIA) triad, 656–657
conflicting permissions, 688
connection-oriented communication
vs. connectionless, 28–29
description, 282–284
connectionless communication
vs. connection-oriented, 28–29
description, 282
connections
10 gigabit Ethernet, 103
cable, 141–146
demarcs, 133–134
NICs, 158–159
patch panels, 146–148
port status, 294–296
Wi-Fi issues, 528–537
connectivity
local and cloud resources, 576–578
WAN. See wide area network (WAN) connectivity
connectors. See cabling and connectors
console ports
routers, 264
switches, 396–397
containerization, 547
content delivery networks (CDNs), 432
content filtering, 700
content switches, 412
context-aware firewalls, 698
contingency planning
business continuity, 647–648
disaster recovery, 646–647
forensics, 648–651
incident response, 645
overview, 645
continuity testers
cable, 733
copper cabling, 149
continuous integration/continuous deployment (CI/CD), 555
Control Plane Policing, 693
control planes
routers, 561
switches, 396
controllers
DCS, 620–621
enterprise wireless, 507
SDN, 562
convergence for routers, 256
converting decimal and binary values, 182–183, 207–209
cooling factors in telecommunications room location, 136
COPE (corporate-owned, personally enabled) deployment model, 633
copper-based 10 GbE, 103
copper cabling
coaxial, 50–54
testing, 148–154
twinaxial, 54
twisted pair, 54–59
core for fiber-optic cabling, 59
core layers in data centers, 585
corporate-owned, business only (COBO) deployment model, 633
corporate-owned, personally enabled (COPE) deployment model, 633
CoS (class of service) in DSCP, 617–618
costs
dynamic routing, 252
OSPF, 261
Counter Mode Cipher Block Chaining Message Authentication Code Protocol (CCMP), 502
counters, performance, 721
couplers, cable, 164–165
CPE (customer premises equipment), 133, 477–478
CRC (cyclic redundancy check), 14, 71
credentials
cleartext, 679–680
default, 692
crimpers
description, 736
patch cables, 142–145
UTP cable, 74
cross-polarization in antennas, 519
crossover cable
inadvertent, 123
routers, 268
switches, 84–85
troubleshooting, 761
crosstalk
cable, 733
copper cabling, 152–153
patch panels, 125
punchdown blocks, 124
twisted pair cable, 54
crypto-malware, 672–673
CSMA/CA (carrier-sense multiple access with collision avoidance), 492–493
CSMA/CD (carrier-sense multiple access with collision detection), 79–81
CTI (computer telephony integration), 614
customer premises equipment (CPE), 133, 477–478
CVE (Common Vulnerabilities and Exposures) database, 659
CWDM (coarse wavelength division multiplexing), 452
cyclic redundancy check (CRC), 14, 71
cyclical log files, 721
CYOD (choose your own device), 633
D
DaaS (desktop as a service), 574–576
DAC (direct attached cable), 54
DAC (discretionary access control) model, 372
DAI (Dynamic ARP Inspection), 665–666
damaged fiber-optic cables, 154
DARPA (Defense Advanced Research Projects Agency), 23
data breaches, 630
data centers
architecture and design, 582–585
assessments, 600–602
audit reports, 601–602
baseline configurations, 600
documentation, 594–602
emergency procedures, 594
environment, 593
high availability, 591–594
locating, 589
network diagrams, 595–597
overview, 581–582
power, 593
review, 602–604
SDN, 590
site surveys, 600–601
spine-and-leaf architecture, 590–591
storage, 587–588
tiers, 583–584
traffic flows, 585–586
virtualization, 589
Data field for frames, 14
Data Link layer, 18–19
data loss prevention (DLP), 631
Data Over Cable Service Interface Specification (DOCSIS), 460
data parts in Ethernet frames, 71
data planes
routers, 561
switches, 396
data storage for data centers, 587–588
data transport in forensics, 650
data virtual local area networks, 400
databases, 304–305
Datagram TLS (DTLS) VPNs, 476
datagrams
description, 27
dB (decibel) loss in cable, 154
DCF (Distributed Coordination Function), 493
DCSs (distributed control systems), 620–622
DDNS (Dynamic DNS), 342–343
DDoS (distributed denial of service) attacks, 667
dead spots in 802.11n, 495
deauthentication (deauth) attacks, 537, 668
decapsulation in OSI seven-layer model, 35
decibel (dB) loss in cable, 154
decimal and binary values, converting, 182–183, 207–209
dedicated instances in cloud computing, 570
dedicated switches in data centers, 584
default credentials, 692
default-free zones (DFZs), 438
default gateways
switches, 397
default routes in routing tables, 238, 241
default subnet masks (DSMs), 202
default user accounts, 688
default VLANs, 400
Defense Advanced Research Projects Agency (DARPA), 23
defense in depth, 657–658
definition files in intrusion detection systems, 416
degradation in fiber-optic cabling, 154–155
delay in dynamic routing, 252
demarcation points (demarcs)
connections, 133–134
DSL, 457
overview, 131–133
WANs, 478–479
demilitarized zones (DMZs) in firewalls, 700–701
denial of service (DoS) attacks, 666–667
dense wavelength division multiplexing (DWDM), 451–452
deployment
cloud computing, 553
mobile models, 632–633
desktop as a service (DaaS), 574–576
destination addresses in Ethernet, 69
Destination entry in routing tables, 236–238
destination host unreachable messages in ICMP, 287
development environments in IaC, 555
device IDs in MAC addresses, 10
devices
configuration troubleshooting, 759
logs, 721
network. See network devices
sensors, 718
unused, 672
WAP saturation, 532
DFZs (default-free zones), 438
dhclient command, 225
DHCP. See Dynamic Host Configuration Protocol (DHCP)
DHCPv6, 435–437
DHCPv6 Prefix Delegation (DHCPv6-PD), 436–437
diagnostics. See also troubleshooting
cabling, 164–165
lights, 162–163
NICs, 163
physical problems, 162
TCP/IP network issues, 347–349
telecommunications rooms, 165–166
toners, 166–168
dictionary password attacks, 669
differentiated services code point (DSCP), 617–618
differentiated services (DiffServ), 617
dig (domain information groper) tool, 346, 742–743
Digital/Intel/Xerox (DIX) standard, 68
Digital Signature Algorithm (DSA), 360
digital signatures in nonrepudiation, 365–366
digital subscriber line (DSL), 456–459
dipole antennas, 516–517
direct attached cable (DAC), 54
direct-sequence spread-spectrum (DSSS), 491
directed broadcasts in routing tables, 241
dirty optical cables, 154–155
disabling
ports, 693
SSID broadcasts, 504
unnecessary services, 677–678, 693
user accounts, 686
disassociation issues in Wi-Fi, 537
disaster recovery, 646–647
Discover messages in DHCP, 215
discovery, Bluetooth, 611
discretionary access control (DAC) model, 372
dispersion in fiber-optic cabling, 155
display filters in protocol analyzers, 715–716
disposal of assets, 672
distance factors in telecommunications room location, 136
distance limitations
couplers, 165
Wi-Fi, 529
distance vector routing protocols, 253–257
distributed control systems (DCSs), 620–622
Distributed Coordination Function (DCF), 493
distributed denial of service (DDoS) attacks, 667
distributed switches, 558
distribution layers in data centers, 585
diverse paths for high availability, 592
divide and conquer troubleshooting approach, 754
DIX (Digital/Intel/Xerox) standard, 68
DKIM (DomainKeys Identified Mail), 342
DMARC (Domain-based Message Authentication, Reporting, and Conformance), 342
DMZs (demilitarized zones) in firewalls, 700–701
DNS. See Domain Name System (DNS)
DNSSEC (DNS Security Extensions), 343, 660
DOCSIS (Data Over Cable Service Interface Specification), 460
documentation
changes, 636
data centers, 594–602
forensics, 649
router setup, 273
troubleshooting, 755–757
Domain-based Message Authentication, Reporting, and Conformance (DMARC), 342
domain controllers, 378
domain information groper (dig) tool, 346, 742–743
Domain Name System (DNS)
cache poisoning, 660
caching, 334–335
client troubleshooting, 343–347
DDNS, 342–343
DNSSEC, 343
forward lookup zones, 336
IPv6, 441–442
load balancing, 411–412
name resolution, 329–333
name servers, 326–327
name spaces, 322–326
overview, 321–322
primary and secondary servers, 327
public servers, 342
records, 336–342
reverse zones, 328
review, 350–352
server administration, 333–343
TCP/IP network issues, 347–349
UDP, 176
WANs, 478
Domain Name System Security Extensions (DNSSEC), 343, 660
DomainKeys Identified Mail (DKIM), 342
domains in Active Directory, 333–334
dongles for NICs, 8
doorbells, 609–610
doors
access controls, 682–683
emergency procedures, 594
smart lockers, 683–684
DoS (denial of service) attacks, 666–667
dots (.)
DNS, 324
IP addresses, 181
dotted decimal notation for IP addresses, 22, 181–182, 207–209
double-tagging VLAN attacks, 406
drivers for NICs, 159–160
drops in Gigabit Ethernet, 97
DSA (Digital Signature Algorithm), 360
DSCP (differentiated services code point), 617–618
DSL (digital subscriber line), 456–459
DSL Access Multiplexer (DSLAM), 457
DSMs (default subnet masks), 202
DSSS (direct-sequence spread-spectrum), 491
DTLS (Datagram TLS) VPNs, 476
dual stacks for IP addresses, 442–444
dumb terminals, 297
duplex
full-duplex Ethernet, 95–96
Gigabit Ethernet, 104
interface monitors, 719
NICs, 74
switches, 399
troubleshooting, 768
duplex fiber-optic cabling, 60
duplicate addresses, troubleshooting, 763
DWDM (dense wavelength division multiplexing), 451–452
Dynamic ARP Inspection (DAI), 665–666
Dynamic DNS (DDNS), 342–343
Dynamic Host Configuration Protocol (DHCP)
configuring, 216–219
description, 285
failures, 223–225
IP addresses, 214–215
IPv6, 435–437
multiple servers, 225–226
operation, 215–216
relay, 219
reservations, 219–222
rogue servers, 226–227
router setup, 271–272
snooping, 662
starvation attacks, 668
troubleshooting, 764
UDP, 176
VLANs, 408–409
dynamic multipoint VPN (DMVPN), 476
dynamic NAT (DNAT), 247
dynamic ports, 290
dynamic protocols in router setup, 273
dynamic routing
benefits, 262
distance vector, 253–257
EIGRP, 261–262
link state, 260–261
metrics, 251–253
overview, 250–251
path vector, 257–260
route redistribution and administrative distance, 262–263
dynamic VLANs, 405
E
clients, 302–303
protocols, 299
secure, 388–389
servers, 300–301
SNMP alerts, 712
spoofing, 660
web, 303–304
EAP (Extensible Authentication Protocol), 498–500
east-west traffic in data centers, 586
ECDSA (Elliptic Curve DSA), 360
echo requests and replies in ICMP, 286–287
ECN (explicit congestion notification), 617–618
ECPM (Equal-Cost Multipath) protocol, 590
EDGE (Enhanced Data rates for GSM Evolution), 463
edge layers in data centers, 584
edge routers, 259
edge security, 688–689
Edit IP Settings dialog, 211
EDNS (Extension Mechanisms for DNS), 343
effective isotropic radiated power (EIRP), 531
effective permissions, 687
effective radiated power (ERP), 531
EGP (Exterior Gateway Protocol), 258–259
EIA (Electronic Industries Alliance), 113–114
8 position 8 contact (8P8C) connectors, 58–59
802.1Q trunk standard, 402
802.1x standard, 500–502
802.11 standard, 485
BSSID, SSID, and ESSID, 490–491
channels, 491–492
CSMA/CA, 492–493
hardware, 485–486
range, 490
software, 487–488
transmission frequencies, 491
transmission methods, 491
802.11a standard, 494
802.11ac standard, 496
802.11ax standard, 496–497
802.11b standard, 493–494
802.11g standard, 494–495
802.11n standard, 495–496
802.3 working group standards, 68–69
802.3a standard, 509
EIGRP (Enhanced Interior Gateway Routing Protocol), 261–262
EIRP (effective isotropic radiated power), 531
elasticity in cloud computing, 569
electromagnetic interference (EMI)
100BASE-FX, 94
coaxial cable, 51
copper cabling, 149
troubleshooting, 761
twisted pair cable, 55
WANs, 478–479
Electronic Industries Alliance (EIA), 113–114
Elliptic Curve DSA (ECDSA), 360
emergency procedures in data centers, 594
EMI. See electromagnetic interference (EMI)
employee training, 638
EN (Europe Norm), 113
Encapsulating Security Payload (ESP), 387
encapsulation
frames, 13
OSI seven-layer model, 35
VPNs, 476
encryption
asymmetric-key, 358–360
with authentication, 385–387
infrastructure networks, 523–524
OSI model, 360–361
overview, 354–355
secure applications, 310
SSH, 381–384
standards, 380–384
substitution ciphers, 355–356
symmetric-key, 357–359
tunneling, 383–384
Wi-Fi, 498
Wi-Fi mismatches, 529
WPA2, 503
XOR operation, 356–357
endpoints
ports, 291
PPTP, 472
tunnel brokers, 445
VPNs, 470–471
Enhanced Data rates for GSM Evolution (EDGE), 463
Enhanced Interior Gateway Routing Protocol (EIGRP), 261–262
enhanced quad small form-factor pluggable connectors, 106–107
enhanced small form-factor pluggable Gigabit Ethernet, 104
enterprise wireless
administration, 506–508
construction, 506
overview, 505–506
PoE, 508–509
VLAN pooling, 508
environment
data centers, 593
monitors, 166
sensors, 718
ephemeral ports, 290
Equal-Cost Multipath (ECPM) protocol, 590
equipment in service-level agreements, 639
equipment racks, 118–122
ERP (effective radiated power), 531
escalating problems, troubleshooting, 754–755, 772
ESP (Encapsulating Security Payload), 387
ESSIDs (extended service set identifiers), 490–491
ESSs (extended service sets), 489
ESX hypervisor, 544
Ethernet
10 gigabit, 100–106
10BASE-FL, 76–78
10BASE-T, 72–76
40 GbE, 106–107
100 GbE, 106–107
100-megabit, 91–96
100BASE-FX, 94–95
100BASE-SX, 95
100BASE-T, 92–94
802.3 working group standards, 68–69
1000BASE-LX, 98–99
1000BASE-SX, 97
bus, 71–72
CSMA/CD, 79–81
evolutions, 100–107
full-duplex, 95–96
Gigabit, 97–100
history, 68
hubs, 81
IP, 177–181
overview, 67
segment connections, 84–86
switches, 81–87
Ethernet frames in IP packets, 178–179
EUI-64 (Extended Unique Identifier, 64-bit), 429
EUIs (Extended Unique Identifiers), 10–15
Europe Norm (EN), 113
event management in SNMP, 712
everything-as-a-service, 574
evidence collection in forensics, 650–651
evil twins APs, 536
Evolved High-Speed Packet Access, 464
Exchange Server, 301
exclusion ranges in DHCP, 220
exclusive OR (XOR) operation in encryption, 356–357
Exim e-mail server, 300
exit plans in emergency procedures, 594
Experimental Bits (Exp) in MPLS headers, 453
explicit congestion notification (ECN), 617–618
explicit denies, 700
extended service set identifiers (ESSIDs), 490–491
extended service sets (ESSs), 489
Extended Unique Identifier, 64-bit (EUI-64), 429
Extended Unique Identifiers (EUIs), 10–15
extending wireless networks, 527
Extensible Authentication Protocol (EAP), 498–500
extensible protocols in SNMP, 709
Extension Mechanisms for DNS (EDNS), 343
extensions for demarcs, 133
Exterior Gateway Protocol (EGP), 258–259
external DNS servers, 333
external firewalls, 701
external threats, 658
externally imposed policies, 634
extranets, 466
F
F connectors, 52
facilities and infrastructure support
data centers, 593–594
telecommunications rooms, 165
facilities performance, 721
factory reset/wipe configuration, 672
fail safe locks in emergency procedures, 594
failover
DHCP, 226
high availability, 592
fair access policies, 772
far-end crosstalk (FEXT), 153
Fast Ethernet, 92
fault tolerance in star topologies, 46
FC (Fibre Channel), 588
FCoE (Fibre Channel over Ethernet), 588
FCS (frame check sequence)
overview, 16–17
FEC (Forwarding Equivalence Class) in MPLS, 454–455
FHRPs (first hop redundancy protocols), 592
FHSS (frequency-hopping spread-spectrum), 491
fiber distribution panels, 133
fiber-optic cabling and connectors
10 GbE, 101–102
10BASE-FL, 76–78
100BASE-FX, 94–95
light meters, 735
network interface units, 132
NICs, 158
overview, 59–62
SFF, 98–99
testing, 154–157
transceivers, 103–105
Fibre Channel (FC), 588
Fibre Channel over Ethernet (FCoE), 588
fifth generation (5G) cellular, 465
file hashing, 361–362
file integrity monitoring (FIM), 726–727
File Transfer Protocol (FTP), 305–306
filters
firewalls. See firewalls
ports, 700
protocol analyzers, 715–716
FIM (file integrity monitoring), 726–727
FIN (final) segments, 283
fire ratings for cable, 63
fire suppression systems, 593
firewalls
advanced techniques and features, 698
DMZs, 700–701
honeypots and honeynets, 701–702
ICMP, 287
implementing and configuring, 699–702
multilayer switches, 415
software vs. hardware, 697–698
troubleshooting, 702–703
virtualization, 558–559
first hop redundancy protocols (FHRPs), 592
Flags entry in routing tables, 236
flags field in TCP, 175
flat-surface connectors, 99
flexibility in virtualization, 547–548
flood guards, 693
flooding, multicast, 767
floor plans
data centers, 595–596
structured cabling, 134–135
flow control with switches, 399
flow monitoring for packets, 716–717
forensics
documentation, 649
evidence collection, 650–651
overview, 648–649
securing areas, 649
forward lookups in DNS, 328, 336
forward proxy servers for multilayer switches, 419
forwarding
port, 247–249
UDP, 219
Forwarding Equivalence Class (FEC) in MPLS, 454–455
forwarding planes
routers, 561
switches, 396
four-post racks, 120
four-way handshakes in DHCP, 216
4to6 tunneling standard, 444–445
Fox and Hound tone generators, 167
FQDNs (fully qualified domain names), 324–326, 332–333
fragmentation with routers, 274
frame check sequence (FCS)
overview, 16–17
frames
central boxes, 15–16
description, 13
frame check sequence, 16–17
movement, 16–19
packets, 24–26
FreeRADIUS, 378
frequencies
802.11, 491
infrastructure networks, 524–525
frequency analysis in code breaking, 356
frequency-hopping spread-spectrum (FHSS), 491
friendly DoS attacks, 668
FTP (File Transfer Protocol), 305–306
full duplex
10BASE-T, 74
Ethernet, 95–96
switches, 399
full tunnel VPNs, 475
fully meshed topology networks, 49
fully qualified domain names (FQDNs), 324–326, 332–333
fusion splicers, 157
G
gain, antenna, 518
garage door openers, 609
Gateway Load Balancing Protocol (GLBP), 592, 770
gateways
routing tables, 236
switches, 397
unified communication, 616
voice, 614
GBICs (gigabit interface converters), 100
GCFA (GIAC Certified Forensic Analyst), 648
generations, cellular, 462
generators
power, 593
telecommunications rooms, 165
Generic Routing Encapsulation (GRE) protocol, 476
Genmask entry in routing tables, 236
geofencing, 505
GET requests
HTTP, 289
SNMP, 710–711
GIAC (Global Information Assurance Certification), 648
GIAC Certified Forensic Analyst (GCFA), 648
Gigabit Ethernet, 97
1000BASE-LX, 98
1000BASE-SX, 97
mechanical connection variations, 99
multiple types, 99–100
SFF fiber connectors, 98–99
gigabit interface converters (GBICs), 100
GLBP (Gateway Load Balancing Protocol), 592, 770
Global Cyber Alliance, 478
global hierarchy in DNS, 321
Global Information Assurance Certification (GIAC), 648
Global System for Mobile Communications (GSM), 462–463
global unicast addresses, 429–430
Gmail, 304
government laws and regulations, 634
Grafana program, 723
graphing programs, 723–724
GRE (Generic Routing Encapsulation) protocol, 476
Greenfield mode in 802.11n, 495
groups in IGMP, 288
GSM (Global System for Mobile Communications), 462–463
guards, security, 681
guest virtual environments, 543
H
H.323 protocol, 616
HA. See high availability (HA)
half duplex
collisions, 768
description, 95
NICs, 74
switches, 399
hands-on problems, troubleshooting, 760–763
handshakes
SSH, 381
hard drives in data centers, 587
hardening networks
agents, 690–691
devices, 692–697
edge, 688–689
Internet of Things, 612–613
physical security, 680–685
posture assessment, 689–690
security policies, 630–634
segmentation, 691–692
user accounts, 685–688
hardware
802.11, 485–486
redundancy, 592
troubleshooting tools, 732–738
underutilization, 542–543
hardware firewalls, 697–698
hashes for integrity, 361–365
headends
cable modems, 460
VPNs, 474
headers
Ethernet, 179
frames, 14
HTTP, 176–177
IP, 173–174
MPLS, 452–454
TCP, 175
UDP, 176
Health Insurance Portability and Accountability Act (HIPAA), 601
heat maps, 511
heating, ventilation, and air conditioning (HVAC) systems, 593
Hello packets in OSPF, 260
helpers in DHCP, 219
hexadecimal numbering system
description, 10
IPv6 addresses, 427
MAC addresses, 9
hextets in IPv6 addresses, 427
HIDSs (host-based IDSs), 416
hierarchical name space in DNS, 321–323
high availability (HA)
data centers, 591–594
disaster recovery, 646–647
environment, 593
facilities and infrastructure support, 593–594
load balancing, 591
redundancy, 592
high fidelity (Hi-Fi), 484
High-Speed Packet Access (HSPA+), 464
high-throughput in 802.11n, 495
HIPAA (Health Insurance Portability and Accountability Act), 601
HIPSs (host-based intrusion prevention systems), 417
HMIs (human–machine interfaces), 622
home automation, IoT, 607–609
home security, IoT, 609–610
honeypots and honeynets, 701–702
hopping, VLAN, 671
hops and hop counts
distance vector routing protocols, 253
dynamic routing, 252
OSPF, 261
routers, 276
routing, 251
horizontal cabling, 115–118
host-based anti-malware, 697
host-based firewalls
description, 698
incorrect settings, 703
multilayer switches, 415
host-based IDSs (HIDSs), 416
host-based intrusion prevention systems (HIPSs), 417
host IDs in IP addresses, 189
host names in DNS, 323–324
host-to-host VPNs, 475
host-to-site VPN connections, 474
hostname utility, 739
hosts
network security, 693–695
subnets, 201
virtual machines, 556–557, 559–560
hosts file, 320–321
hot sites, 647
Hot Standby Router Protocol (HSRP), 592
HSPA+ (High-Speed Packet Access), 464
HSRP (Hot Standby Router Protocol), 592
HTML (Hypertext Markup Language), 307–308
HTTP (Hypertext Transfer Protocol)
browsers, 307–311
GET requests, 289
headers, 176–177
HTTPS (Hypertext Transfer Protocol Secure), 309–311, 387–388
HTTPS/management URLs for switches, 397
hub-and-spoke topologies, 46–47
hubs
frames, 15
human–machine interfaces (HMIs), 622
humidity factors in telecommunications room location, 136, 166
Hurricane Electric tunnel brokers, 445
HVAC (heating, ventilation, and air conditioning) systems, 593
hybrid clouds, 553
hybrid routing protocols, 259
hybrid topologies, 47–48
HyperTerminal program, 264
Hypertext Markup Language (HTML), 307–308
Hypertext Transfer Protocol (HTTP)
browsers, 307–311
GET requests, 289
headers, 176–177
Hypertext Transfer Protocol Secure (HTTPS), 309–311, 387–388
hypervisors
Rocket.Chat platform setup, 564–568
virtualization, 543–546
I
IaaS (infrastructure as a service)
overview, 550–551
Rocket.Chat setup, 571–573
IaC (Infrastructure as code), 554–556
IACIS (International Association of Computer Investigative Specialists), 648
IANA (Internet Assigned Numbers Authority), 258
IP addresses, 197
port recommendations, 290
IAS (Internet Authentication Service), 378
IBSSs (independent basic service sets), 488
ICA (Independent Computing Architecture), 467
ICANN (Internet Corporation for Assigned Names and Numbers), 198, 322
ICMP (Internet Control Message Protocol), 173, 286–287
ICSs (industrial control systems), 619–620, 625
IDFs (intermediate distribution frames)
data centers, 596–598
demarcs, 133–134
description, 118
IEEE (Institute of Electrical and Electronics Engineers) cabling standards, 63–64
IEFT. See Internet Engineering Task Force (IETF)
Iface entry in routing tables, 236
ifconfig command
DHCP, 225
IP and MAC addresses, 186–187
IPv6, 437
MAC addresses, 10
overview, 740
IFG (interframe gap) in CSMA/CA, 492–493
IGMP (Internet Group Management Protocol)
overview, 288
snooping, 766–767
IGPs (Interior Gateway Protocols), 258–259
illegal use in acceptable use policies, 630
IMAP4 (Internet Message Access Protocol version 4), 299
IMAPS (Internet Message Access Protocol over SSL), 389
impact factor in change management, 635
impedance of cable
description, 53
mismatch, 733
implicit denies, 700
in-band management
switches, 397–398
VNCs, 469
inbound firewall traffic, 700
incident response, 645
incompatibilities in Wi-Fi, 536
independent basic service sets (IBSSs), 488
Independent Computing Architecture (ICA), 467
industrial control systems (ICSs), 619–620, 625
information gathering in troubleshooting, 751
infrastructure as a service (IaaS)
overview, 550–551
Rocket.Chat setup, 571–573
Infrastructure as code (IaC), 554–556
infrastructure layer in SDN, 561
infrastructure mode in 802.11, 489
infrastructure networks
antennas, 515–520
channels and frequency, 524–525
client configuration, 526
encryption, 523–524
MAC address filtering, 522
SSIDs, 521–522
WAPs, 520–522
inputs in virtualization, 547–548
insider threats, 669–671
installation of physical networks. See physical network installation
Institute of Electrical and Electronics Engineers (IEEE) cabling standards, 63–64
insufficient wireless coverage, 529
insulating jackets for fiber-optic cabling, 59
integrity
CIA triad, 656
inter-VLAN routing, 407–408
interconnecting LANs, 190–192
interface errors
troubleshooting, 761
WANs, 477–478
interface IDs in IPv6 addresses, 427
interfaces
DCS, 622
monitoring, 719–720
switch configuration, 397–398
troubleshooting, 759–760
interference
100BASE-FX, 94
cabling, 148–149
coaxial cable, 51
troubleshooting, 761
twisted pair cable, 55
WANs, 478–479
interframe gap (IFG) in CSMA/CA, 492–493
Interior Gateway Protocols (IGPs), 258–259
intermediate distribution frames (IDFs)
data centers, 596–598
demarcs, 133–134
description, 118
Intermediate System to Intermediate System (IS-IS), 261
internal DNS servers, 333
internal firewalls, 701
internal threats, 658
International Association of Computer Investigative Specialists (IACIS), 648
International Society of Forensic Computer Examiners (ISFCE), 648
International Telecommunication Union (ITU), 451
Internet Assigned Numbers Authority (IANA), 258
IP addresses, 197
port recommendations, 290
Internet Authentication Service (IAS), 378
Internet Control Message Protocol (ICMP), 173, 286–287
Internet Corporation for Assigned Names and Numbers (ICANN), 198, 322
Internet Engineering Task Force (IETF), 258
IPsec, 386–387
IPv6, 425–426
private IP addresses, 227
VoIP, 614
Internet Group Management Protocol (IGMP)
overview, 288
snooping, 766–767
Internet Message Access Protocol over SSL (IMAPS), 389
Internet Message Access Protocol version 4 (IMAP4), 299
Internet of Things (IoT), 607
communications technologies, 610–612
hardening, 612–613
home automation, 607–609
home security, 609–610
Internet Protocol (IP), 22, 282
addresses. See IP addresses
Ethernet, 177–181
Internet Protocol Security (IPsec), 386–387
Internet Protocol version 4 (IPv4) addresses, 173. See also IP addresses
Internet Protocol Version 4 (TCP/IPv4) Properties dialog, 211, 329–330
Internet Protocol version 6 (IPv6)
aggregation, 438–441
anycast addresses, 432
DNS, 441–442
global unicast addresses, 429–430
link-local addresses, 428–429
moving to, 442–446
multicast addresses, 430–432
neighbor discovery, 432–434
notation, 426–428
overview, 425–426
Regional Internet Registries, 430
review, 446–448
SLAAC implementation, 434–438
testing, 437–438
Internet service providers (ISPs), 592
Internet Small Computer System Interface (iSCSI), 588
Internet Society (ISOC), 258
intrusion detection systems (IDSs), 415
intrusion in cloud computing, 570
intrusion prevention systems (IPSs), 416–417
IOS operating system, 265–267
IoT. See Internet of Things (IoT)
ip address command
IP and MAC addresses, 187–188
IPv6, 437
IP addresses
ARP cache poisoning, 663
assigning, 209–210
class IDs, 197–199
dual stacks, 442–444
dynamic. See Dynamic Host Configuration Protocol (DHCP)
example, 181–188
headers, 173–174
IPv6. See Internet Protocol version 6 (IPv6)
LAN interconnections, 190–192
and MAC, 178–180
multilayer switches, 411–412
name resolution. See Domain Name System (DNS)
network address translation, 244–250
network IDs, 188–189
routing tables, 235
special, 227
spoofing, 660
static, 210–214
subnet masks, 192–197
subnets, 199–209
switches, 397
troubleshooting, 761–764
IP cameras, 685
ip command
IP information, 212–214
MAC addresses, 10–11
overview, 740
routing tables, 760
ip helper-address command, 409
IP packets in Ethernet frames, 178–179
ip route command, 239
ipconfig command
IPv6, 437
overview, 740–741
ipconfig /all command
IP addresses, 185–186
overview, 740
ipconfig /flushdns command, 344
ipconfig /registerdns command, 343
ipconfig /release command, 225
ipconfig /renew command, 225
iPerf tool, 725
IPsec (Internet Protocol Security), 386–387
IS-IS (Intermediate System to Intermediate System), 261
ISFCE (International Society of Forensic Computer Examiners), 648
ISO 27001 standard, 601
ISO 27002 standard, 601
isolation in Wi-Fi, 504–505
iterative DNS lookups, 332–333
ITU (International Telecommunication Union), 451
J
jacks
connections, 141–142
DSL, 458
jitter
copper cabling, 153
WAPs, 532–533
jumbo frames
iSCSI, 588
switches, 399
K
Kahn, Robert E., 23
Kali Linux bootable USB drives, 644
Keks, Anton, 747–748
Kerberos authentication, 378–380
Kerberos Key Distribution Center (KDC) service, 379
keypads, 682
keys
locks, 681–682
public-key cryptography, 359–360
SSH, 382–383
Krone blocks, 127
L
L2F (Layer 2 Forwarding), 474–475
L2TP (Layer 2 Tunneling Protocol), 474–475
Label Distribution Protocol (LDP), 454
label edge routers (LERs), 454–455
label switching routers (LSRs), 454–455
labels
MPLS headers, 453–455
outlets, 129
patch panels, 124–125
LACNIC (Latin American and Caribbean Internet Addresses Registry), 430
LACP (Link Aggregation Control Protocol)
multilayer switches, 414
NICs, 160
troubleshooting, 765–766
LANs. See local area networks (LANs)
last-mile technologies
broadband cable, 459–460
cellular, 461–465
DSL, 456–459
fiber, 461
satellites, 460–461
latency
802.11a, 494
copper cabling, 153
dynamic routing, 252
spine-and-leaf architecture, 590
WAPs, 532–533
Latin American and Caribbean Internet Addresses Registry (LACNIC), 430
laws and regulations, 634
Layer 2 data routing, 235–243
Layer 2 Forwarding (L2F), 474–475
Layer 2 Tunneling Protocol (L2TP), 474–475
Layer 3 capable switches, 233
LCs (local connectors), 61–62, 98–99
LDAP (Lightweight Directory Access Protocol), 391
LDAPS (Lightweight Directory Access Protocol over SLL), 391
LDP (Label Distribution Protocol), 454
LEAP (Lightweight EAP), 499
leased lines in WANs, 452
leases, DHCP, 216
LEDs (light-emitting diodes)
fiber-optic cabling, 60
NICs, 160–163
troubleshooting, 761
legacy mode in 802.11n, 495
legacy systems, 679
legal holds in forensics, 650–651
length of passwords, 638
LERs (label edge routers), 454–455
lessons learned in troubleshooting, 756
licensed feature issues, troubleshooting, 769
light-emitting diodes (LEDs)
fiber-optic cabling, 60
NICs, 160–163
troubleshooting, 761
light leakage in fiber-optic cabling, 155
light meters for fiber, 735–736
lights-out-management (LOM), 469
Lightweight Access Point Protocol (LWAPP), 508
Lightweight Directory Access Protocol (LDAP), 391
Lightweight Directory Access Protocol over SLL (LDAPS), 391
Lightweight EAP (LEAP), 499
Link Aggregation Control Protocol (LACP)
multilayer switches, 414
NICs, 160
troubleshooting, 765–766
link lights in NICs, 160–163
link-local addresses, 225, 428–429
link state
802.11, 487
monitoring, 725
link state advertisement (LSA) packets in OSPF, 260
link state dynamic routing protocols, 260–261
listening ports, 294
LiveAction tool, 717
LLC (Logical Link Control), 20
load balancing
high availability, 591
multilayer switches, 410–412
local access in network security, 669–672
local area networks (LANs)
full-duplex Ethernet, 96
interconnecting, 190–192
router setup, 272–273
TCP/IP, 177–178
virtual. See virtual LANs (VLANs)
wireless controllers, 507
local authentication in TCP/IP security, 370
local connectors (LCs), 61–62, 98–99
local port mirroring, 417
local resources, cloud computing interconnections with, 576–578
lockers, smart, 683–684
locking racks, 120
locks
emergency procedures, 594
physical security, 681–683
logic bombs, 673
logical addresses, 21–22
Logical Link Control (LLC), 20
logical network diagrams, 598–599
logical topologies, 48
logs
cloud computing, 570
performance, 720–721
syslog, 725
LOM (lights-out-management), 469
Long Term Evolution (LTE) technology, 464–465
looking glass sites, 749
lookup zones in DNS, 327–328
loopback adapters, 735
loopback addresses
description, 227
IPv6 addresses, 428
routing tables, 241
loopback tests for NICs, 163
loops
routing tables, 242
LSA (link state advertisement) packets in OSPF, 260
LSRs (label switching routers), 454–455
LTE (Long Term Evolution) technology, 464–465
LWAPP (Lightweight Access Point Protocol), 508
Lyon, Gordon, 641
M
MAC addresses. See media access control (MAC) addresses
MAC (mandatory access control) security model, 372
macros, 673
mail exchange (MX) DNS records, 340–341
main distribution frames (MDFs)
data centers, 596–598
demarcs, 133–134
telecommunications rooms, 118
maintenance windows in change management, 636
malformed packets, 661
malicious users, 670–671
malware
anti-malware programs, 696–697
dealing with, 696
prevention and recovery, 693–695
training, 638
types, 672–674
man-in-the-middle attacks
ARP cache poisoning, 665
CHAP for, 374
description, 668
managed devices, 264
managed networks in SNMP, 709
Management Information Bases (MIBs) in SNMP, 390, 709
management planes in SDN, 563
management ports for switches, 397
managers in SNMP, 709
mandatory access control (MAC) security model, 372
MANs (metropolitan area networks), 455
mantraps, 682
maps
runs, 135–136
wire, 150
masks, subnet. See subnet masks
mass storage devices in data centers, 587
maximum transmission units (MTUs) for routers, 274–275
MD5 (Message-Digest Algorithm version 5) algorithm
EAP, 499
hashes, 363
MDFs (main distribution frames)
data centers, 596–598
demarcs, 133–134
telecommunications rooms, 118
MDM (mobile device management) system, 634
mean time between failures (MTBF), 646
mean time to failure (MTTF), 647
mean time to repair (MTTR), 647
Mechanical Transfer Registered Jack (MT-RJ) connectors, 61–62, 98–99
media access control (MAC) addresses
ARP cache poisoning, 662–663
central boxes, 15–16
determining, 12
Ethernet frames, 69–70
MAC-48 and EUI-48, 10–15
NICs, 9–21
reservations, 221
spoofing, 660
TCP/IP, 23–24
troubleshooting, 763
media converters
10BASE-FL, 77–78
Gigabit Ethernet, 100
Media Gateway Control Protocol (MGCP), 616–617
medianets, 617–618
meetings, Zoom, 312–313
megahertz (MHz) category ratings, 56
memoranda of understanding (MOUs), 639
Meraki dashboard, 508
mesh topologies
802.11, 488
wireless technologies, 48–49
Message-Digest Algorithm version 5 (MD5) algorithm
EAP, 499
hashes, 363
message digests, 361–363
Metasploit tool, 643
Metric entry in routing tables, 236
metrics
network, 718–719
OSPF, 261
routing, 251–253
routing tables, 239–240
metro Ethernet networks, 455
metropolitan area networks (MANs), 455
MFA (multifactor authentication), 371, 683
MFDs (multifunction devices), 609
MGCP (Media Gateway Control Protocol), 616–617
mGRE (multipoint GRE) protocol, 476
MHz (megahertz) category ratings, 56
MIBs (Management Information Bases) in SNMP, 390, 709
micro prefix, 60
MicroScanner tool, 150
microsegmentation, 691
Microsoft Exchange Server, 301
Microsoft Outlook, 302–303
Microsoft Teams, 312–313
MIMO (multiple input/multiple output), 495, 531
mirroring, port
overview, 417
packet sniffers, 713
misconfigured firewalls, 702
mismatches
cable impedance, 733
cable termination, 761
fiber-optic cabling, 155
VLAN, 765
Wi-Fi security, 529
missing routes, 274
mitigating vulnerabilities, 659
mixed mode
802.11g, 494
802.11n, 495
MLSs. See multilayer switches (MLSs)
MMF (multimode fiber)
10BASE-FL, 76
fiber-optic cabling, 61
MMSs (multimedia messaging systems), 464
mobile deployment models, 632–633
mobile device management (MDM) system, 634
modal dispersion in fiber-optic cabling, 155
modal distortion in fiber-optic cabling, 61
modems
DSL, 458
WANs, 477–478
modes
802.11g, 494
wireless networks, 487–489
modules in data centers, 584
monitoring
network. See network monitoring
physical security, 684–685
monlist queries, 661
motion detection systems, 685
MOUs (memoranda of understanding), 639
MPLS (Multiprotocol Label Switching), 452–454
MS-CHAP, 374–375
MSAs (multi-source agreements), 103, 639
MT-RJ (Mechanical Transfer Registered Jack) connectors, 61–62, 98–99
MTBF (mean time between failures), 646
mtr (My Traceroute) utility, 276, 743–744
MTTF (mean time to failure), 647
MTTR (mean time to repair), 647
MTUs (maximum transmission units) for routers, 274–275
MU-MIMO (multiuser MIMO), 496, 531
multi-source agreements (MSAs), 639
multicast class blocks, 198
multicast flooding, troubleshooting, 767
multicasts
IPv6 addresses, 430–432
packets, 198
multifactor authentication (MFA), 371, 683
multifunction devices (MFDs), 609
multifunction network devices, 410
multilayer switches (MLSs)
description, 233
intrusion detection/intrusion prevention, 415–417
load balancing, 410–412
network protection, 414–421
overview, 409–410
port bonding, 414
QoS and traffic shaping, 413–414
multimedia messaging systems (MMSs), 464
multimeters for cable testing, 150–151, 736–737
multimode fiber (MMF)
10BASE-FL, 76
fiber-optic cabling, 61
multipaths, 591
SANs, 588
Wi-Fi, 534
multiple access in CSMA/CD, 79–81
multiple DHCP servers, 225–226
multiple input/multiple output (MIMO), 495, 531
multiple Internet service providers, 592
multiple problems, troubleshooting, 752
multipoint GRE (mGRE) protocol, 476
Multiprotocol Label Switching (MPLS), 452–454
multisource agreements (MSAs), 103
multispeed lights for NICs, 161
multitenancy in cloud computing, 570
multiuser MIMO (MU-MIMO), 496, 531
MX (mail exchange) DNS records, 340–341