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Book Description

Get the definitive reference for deploying, configuring, and supporting Office Communications Server 2007 with expert insights direct from the Microsoft Office Communications Server Team. This official Microsoft RESOURCE KIT delivers in-depth technical guidance on architecture, deployment, security, administration, performance tuning, and troubleshooting Communications Server 2007. You ll also discover the essential information for working with VOIP and phone integration features. In addition, you get more than 150 timesaving scripts, tools, and other job aids for automating administration, plus an eBook for the entire RESOURCE KIT on CD.
Provides the information that every administrator needs about troubleshooting, security enhancements, phone integration, VOIP, group policy and automating administration

CD includes additional job aids and a fully searchable version of the entire RESOURCE KIT book

Table of Contents

  1. Microsoft Office Communications Server 2007 Resource Kit
    1. Foreword
    2. Acknowledgments
      1. Personal Acknowledgments from Individual Authors
        1. Personal Acknowledgments from Individual Authors
    3. Introduction
      1. What's New in Office Communications Server 2007
      2. Overview of the Book
      3. Document Conventions
        1. Reader Aids
        2. Sidebars
        3. Command-line Examples
      4. Companion CD
        1. Resource Kit Support Policy
    4. I. Overview and Architecture
      1. 1. Overview of Office Communications Server 2007
        1. The Evolution of Office Communications Server 2007
        2. Understanding the Enhanced Presence Model
        3. Overview of IM Conferencing Capabilities
        4. Overview of Web Conferencing Capabilities
        5. Overview of Audio/Video Conferencing Capabilities
        6. Overview of Enterprise Voice Capabilities
        7. Overview of Office Communications Server Clients
        8. Customizing the Platform
          1. Microsoft Unified Communications AJAX SDK
          2. Microsoft Unified Communications Managed API SDK
          3. Microsoft Unified Communications Client API SDK
          4. Microsoft Office Communicator 2007 SDK
          5. Microsoft Office Communications Server 2007 SDK
        9. Summary
        10. Additional Resources
          1. On the Companion CD
      2. 2. Server Roles
        1. Standard Edition Server
        2. Enterprise Edition Pool
        3. Director Role
        4. Conferencing Servers
          1. IM Conferencing Server
          2. Web Conferencing Server
          3. A/V Conferencing Server
          4. Telephony Conferencing Server
        5. Archiving and CDR Server
        6. Edge Servers
          1. Access Edge Server
          2. Web Conferencing Edge Server
          3. A/V Edge Server
        7. Communicator Web Access
        8. Web Components Server
        9. Mediation Server
        10. Supported Collocation Server Roles
        11. Summary
        12. Additional Resources
          1. On the Companion CD
      3. 3. Infrastructure and Security Considerations
        1. Understanding How Office Communications Server Leverages Active Directory
          1. Performing the Prep Schema Step
          2. Performing the Prep Forest Step
          3. Performing the Prep Domain Step
        2. Using DNS to Publish Office Communications Server
        3. Securing Office Communications Server with PKI
          1. Configuring the Common Name or Subject Name
          2. Configuring the Subject Alternative Name
          3. Configuring the CRL Distribution Points
          4. Configuring for Enhanced Key Usage
            1. Server Authentication
            2. Client Authentication
          5. Configuring the Certification Path
        4. Scaling with SQL Server
        5. Building Redundancy with Hardware Load Balancing
        6. Bridging VoIP to the PSTN Network by Using a Media Gateway
        7. Publishing Web Interfaces to the Internet by Using HTTPS Reverse Proxy
        8. Summary
        9. Additional Resources
          1. On the Companion CD
    5. II. Key Usage Scenarios
      1. 4. Basic IM and Presence Scenarios
        1. Understanding the Login Process
          1. Why Talk About the Login Process?
          2. Overview of the Login Process
            1. Step 1: Signing In to an Account
            2. Step 2: Supplying Account Credentials (If Prompted)
            3. Step 3: The Login Process
            4. Step 4: Login Complete
          3. Examining the Technical Details Behind the Login Process
            1. Examining What Happens During the Initial Launch of Communicator 2007 (Pre-Step 1)
            2. Examining What Happens After Sign-In Starts (Post Step 1)
            3. Examining What Happens During Login Processing (Step 3)
            4. Understanding Post-Login Processing (Post-Step 4)
        2. Understanding How Presence Information Is Shared
          1. What Is Presence?
          2. Overview of the Presence Sharing Scenario
            1. Step 1: Looking Up a Contact
            2. Step 2: Adding a Contact
            3. Step 3: Receiving an Offline Indication
            4. Step 4: Logging In the Contact and Receiving Updated Presence Information
            5. Step 5: Controlling the Access Level of a Contact
          3. Examining the Technical Details Behind the Presence Sharing Scenario
            1. Examining What Happens During Looking Up a Contact (Step 1)
            2. Examining What Happens When Adding a Contact (Step 2)
            3. Examining What Happens When Subscribing for Presence and Receiving an Offline Notification (Step 3)
            4. Examining What Happens When the Contact Logs In and Updated Presence Is Received (Step 4)
            5. Examining What Happens When Controlling the Access Level of a Contact (Step 5)
        3. Understanding Instant Messaging
          1. Overview of the Instant Messaging Scenario
            1. Step 1: Opening a Messaging Window
            2. Step 2: Typing and Sending a Message
            3. Step 3: Receiving the Message
            4. Step 4: Sending a Hyperlink
            5. Step 5: Sending a File
            6. Step 6: Sharing Video
            7. Step 7: Ending the Conversation
          2. Examining the Technical Details Behind the Instant Messaging Scenario
            1. Examining What Happens During Session Establishment and Sending a Message (Post Step 2)
            2. Examining What Happens When Receiving a Message (Step 3)
            3. Examining What Happens When Sending a Hyperlink (Step 4)
            4. Examining What Happens When Sending a File (Step 5)
            5. Examining What Happens When Sharing Video (Step 6)
            6. Examining What Happens When Ending the Conversation (Step 7)
        4. Summary
        5. Additional Resources
          1. On the Companion CD
      2. 5. Conferencing Scenarios
        1. Overview of Conferencing Scenarios
          1. Understanding Conferencing User Types
            1. Understanding Authenticated Enterprise Users
            2. Understanding Federated Users
            3. Understanding Anonymous Users
          2. Understanding Conferencing User Roles
          3. Understanding Conference Security and Access Types
            1. Understanding the Open Authenticated Conference
            2. Understanding the Closed Authenticated Conference
            3. Understanding the Anonymous Allowed Conference
          4. Understanding Conferencing Media Types
            1. Understanding Multiparty Instant Messaging
            2. Understanding Data Collaboration
            3. Understanding Audio and Video Conferencing
            4. Understanding Audio Conferencing Provider Support
        2. Examining the Technical Details Behind Conferencing Scenarios
          1. Understanding the Conferencing Architecture
            1. Understanding Conferencing Clients
            2. Understanding the Conferencing Database
            3. Understanding Focus
            4. Understanding the Focus Factory
            5. Understanding Conferencing Servers and the Conferencing Server Factory
            6. Understanding Web Components
            7. Understanding Process and Machine Boundaries for Conferencing Components
            8. Understanding Edge Servers
            9. Understanding the Conferencing Protocols
          2. Understanding the Conference Life Cycle
            1. Understanding Conference Creation
            2. Understanding Conference Activation
            3. Understanding Conference Deactivation
            4. Understanding Conference Expiration
          3. Examining the Technical Details Behind Web Conferencing
            1. Understanding the Client Conference Joining Sequence
            2. Understanding the Client Join Sequence to the Web Conferencing Server
            3. Understanding Conference Control
            4. Understanding Web Conferencing Server Content Management
            5. Understanding Web Conferencing Server Content Upload and Download
            6. Understanding Meeting Compliance
            7. Understanding Web Conferencing Content Tools
            8. Understanding Meeting Policy and Policy Enforcement
        3. Summary
        4. Additional Resources
          1. On the Companion CD
      3. 6. Remote Access Scenarios
        1. Understanding Basic Remote Access Topologies
          1. Single Edge Server
          2. Single-Site Edge Topology
          3. Multisite Edge Topology
        2. Understanding Basic Remote Access Scenarios
          1. Understanding Basic Remote Access for IM and Presence
            1. Examining the Basic Remote Access Scenario in Detail
          2. Understanding Web Conferencing Remote Access
            1. Use Office Communicator to Start a Conference (Step 1)
            2. Accept and Join a Web Conferencing Invitation (Step 2)
            3. Begin Sharing an Application (Step 3)
            4. Examining the Web Conferencing Remote Access Scenario in Detail
          3. Understanding Audio and Video Conferencing Remote Access
        3. Understanding Extended Remote Access Scenarios
          1. Enabling Office Communicator Web Access 2007
          2. Enabling Office Communicator Mobile Access 2007
            1. Examining a COMO Topology
            2. Deploying Certificates for COMO
        4. Summary
        5. Additional Resources
          1. On the Companion CD
      4. 7. Federation Scenario
        1. Understanding Federation
          1. Understanding Direct Federation
          2. Understanding Federated Partner Discovery
          3. Understanding Federation with Public IM Providers
        2. Understanding the Requirements for and Use of Certificates in Federation
          1. Understanding Subject Alternate Name
          2. Understanding TLS Certificates
        3. Comparing Consolidated Topology to Expanded Topology
        4. Understanding On-Premises Conferencing Rules for Federated and Nonfederated Users
        5. Configuring and Administering Federation
          1. Configuring an Edge Server for Federation
          2. Configuring User Accounts for Federation
          3. Administering Federated Partner Access
          4. Managing Multiple User Accounts
          5. Blocking External Domains
        6. Examining the Technical Details Behind the Federation Scenario
          1. Examining How Clients from Two Federated Domains Get Online and Register Presence
            1. Step 1—REGISTER sip:contoso.com SIP/2.0
            2. Step 3—SUBSCRIBE sip:[email protected] SIP/2.0
            3. Step 5—SERVICE sip:[email protected] SIP/2.0
          2. Examining Communication from One Federated Enterprise to Another
            1. Step 1—SUBSCRIBE sip:[email protected] SIP/2.0
            2. Step 2—BENOTIFY and OK/200
            3. Step 8—INVITE sip:[email protected] SIP/2.0
            4. Step 12—INFO sip:[email protected];opaque=user:epid:rcCqh5A6AVmnmbRnI5LzvwAA;gruu SIP/2.0
            5. Step 13—MESSAGE sip:[email protected];opaque=user:epid:IAnGIHUus1qSUt8ED60SDgAA;gruu SIP/2.0
            6. Step 19—sip:[email protected];opaque=user:epid:IAnGIHUus1qSUt8ED60SDgAA;gruu SIP/2.0
        7. Summary
        8. Additional Resources
          1. On the Companion CD
      5. 8. Public IM Connectivity Scenario
        1. Why Talk About the Public IM Connectivity Scenario?
        2. Overview of the Public IM Connectivity Scenario
          1. Considerations for Deploying the Public IM Connectivity Scenario
          2. Enabling Federation with Public IM Service Providers
            1. Provisioning Federation with a Public IM Service Provider
            2. Configuring IM Service Providers
          3. Considerations Involving Public IM Providers
          4. Considerations Involving Existing Accounts on Provider Networks
            1. How the Provider Migrates Existing MSN Accounts
          5. Capacity Planning Considerations
          6. Security Considerations
            1. Controlling Spim by Limiting Public Contacts
            2. Controlling SPIM by Limiting Message Content
          7. Considerations Involving Media Sharing
          8. Enabling Users for Public IM Connectivity
            1. Configuring Per-User and Global Settings
        3. Examining the Technical Details Behind the Public IM Connectivity Scenario
          1. Scenario One: Adding a Contact in Office Communicator 2007
            1. Step 1: Specify Recipient's Account
            2. Step 2: Recipient's Presence Displayed as Unknown
            3. Step 3: Recipient's Account Added as a Contact
            4. Step 4: Recipient's Presence Displayed as Offline
            5. Step 5: Recipient Receives Notification
            6. Step 6: Recipient Adds a User to Buddy List
            7. Step 7: Recipient's Presence Displayed as Online
          2. Scenario Two: Sending a Single Message
            1. Step 1: User Selects a Recipient from the Buddy List in Office Communicator
            2. Step 2: User Types a Message to a Recipient
            3. Step 3: Recipient Receives a Message from a User
            4. Step 4: Recipient Types a Reply to the User
            5. Step 5: User Receives a Message from the Recipient
            6. Step 6: Conversation Finished
        4. Summary
        5. Additional Resources
          1. On the Companion CD
      6. 9. Understanding Remote Call Control Scenario
        1. Why Consider Remote Call Control?
          1. Overview of Remote Call Control Scenario
          2. Technical Details Behind the Remote Call Control Scenario
          3. Setting Up the Remote Call Control Scenario
            1. Installing the CSTA Gateway and Configuring the SIP/CSTA Interface on the PBX or IP PBX
            2. Configuring a User for RCC
            3. Configuring a Route on the Office Communications Server Pool for Server URI
            4. Starting Communicator 2007
        2. Summary
        3. Additional Resources
          1. On the Companion CD
      7. 10. VoIP Scenarios
        1. What Is VoIP?
        2. Overview of VoIP Scenarios
          1. Using Two-Party Calling
          2. Configuring Call Deflection
          3. Configuring Call Forwarding
          4. Using Voice Mail
          5. Using Ad Hoc Conference Calling
        3. Examining the Technical Details Behind VoIP Scenarios
          1. Understanding How Outbound Calls Are Routed
            1. Understanding Voice Policies
            2. Understanding Phone Usage
            3. Understanding Phone Routes
          2. Understanding How Inbound Calls Are Routed
          3. Understanding Normalization
            1. Configuring Global Enterprise Voice Settings
            2. Configuring Voice Policies
            3. Configuring Phone Routes
            4. Configuring Location Profiles
        4. Configuring VoIP
          1. Configuring Users for Unified Communications
          2. Configuring the Media Gateway
          3. Configuring the Mediation Server
          4. Configuring the QoE Monitoring Server
          5. Configuring the Deployment Validation Tool Server
            1. Configuring the DVT Organizer
            2. Configuring the DVT Agent
            3. Managing DVT by Using the Administrative Console
        5. Summary
        6. Additional Resources
          1. On the Companion CD
    6. III. Planning and Deployment
      1. 11. Office Communications Server 2007 Planning Example
        1. Understanding Contoso's Infrastructure
          1. Understanding Contoso's User Distribution
          2. Understanding Contoso's Server Infrastructure
          3. Understanding Contoso's Active Directory Infrastructure
          4. Understanding Contoso's Network Infrastructure
          5. Understanding Contoso's Telephone Infrastructure
        2. Defining the Deployment Goals
          1. Defining the Scenario Selection
          2. Defining the Reliability Requirements
          3. Defining the Compliance Requirements
        3. Understanding Contoso's Office Communications Server 2007 Planning Process
          1. Step 1: Determining Key Planning Decisions
          2. Step 2: Select Your Topology
          3. Step 3: Plan Your Deployment Path
          4. Step 4: Prepare Your Infrastructure
          5. Step 5: Review System and Network Requirements
          6. Step 6: Plan for External User Access
          7. Step 7: Plan for Deploying Load Balancers
          8. Step 8: Plan for VoIP
          9. Step 9: Plan for Address Book Server
          10. Step 10: Plan for High Availability and Fault Tolerance
          11. Step 11: Plan for Database Storage
          12. Step 12: Plan for Compliance and Usage Analysis
        4. Summary
        5. Additional Resources
          1. On the Companion CD
      2. 12. Office Communications Server 2007 Deployment Example
        1. Understanding Contoso's Deployment Process for Office Communications Server 2007
          1. Establishing a Server Naming Convention
          2. Preparing the Server Hardware
          3. Contoso's Deployment Path
            1. Preparing Active Directory
            2. Overview of Preparing Firewall Ports, Certificates, NICs, and DNS
            3. Preparing DNS, Firewall Ports, and Certificates for Chicago Deployment
            4. Preparing DNS and Firewall Ports for the Paris Deployment
            5. Preparing DNS and Firewall Ports for the Madrid Deployment
            6. Preparing DNS and Firewall Ports for the Singapore Deployment
            7. Contoso's Deployment Path for Chicago
            8. Contoso's Deployment Path for Paris
            9. Contoso's Deployment Path for Madrid
            10. Contoso's Deployment Path for Singapore
        2. Final Contoso Architecture
        3. Summary
        4. Additional Resources
          1. On the Companion CD
    7. IV. Operations
      1. 13. Monitoring
        1. Monitoring Office Communications Server by Using the Admins Tools
          1. Monitoring Overall Status by Using the Status Pane
          2. Monitoring Events by Using the Event Log Tab
            1. Using Event Log Filters
            2. Understanding Event Categories
            3. Understanding Event Types
          3. Monitoring Performance by Using the Performance Tab
            1. Using the Performance Monitor
        2. Monitoring Office Communications Server 2007 by Using Microsoft Operations Manager 2005
          1. Using Computer Groups
          2. Using Events and Performance Counters
          3. Using Alerts
          4. Using Tasks
        3. Monitoring Office Communications Server Usage by Using Call Detail Records
          1. Prerequisites for Deploying the Archiving and CDR Service
          2. Deploying the Archiving and CDR Service
          3. Monitoring Usage
          4. Reporting Usage Data
          5. Database Schema for the Archiving and CDR Database
        4. Summary
        5. Additional Resources
          1. On the Companion CD
      2. 14. Backup and Restore
        1. Planning for Backup and Restore
          1. Backup and Restore Requirements
          2. Determining What Needs to Be Backed Up
          3. Backing Up Settings
            1. Backing Up Pool and Global Settings
            2. Backing Up Server Settings
          4. Backing Up Data
            1. Backing Up Databases
            2. Backing Up File Shares
        2. Restoring Service
          1. Deciding How to Restore Service
          2. Verifying Restoration Prerequisites
          3. Setting Up Server Platforms
            1. Preparing to Use the Hardware and Software of an Existing Server for Database Recovery
            2. Recovering an Existing Server
            3. Reinstalling an Existing Server
            4. Rebuilding a Server on New Hardware
            5. Building Standby Servers
          4. Installing Restoration Tools
          5. Restoring Data
            1. Restoring Databases
            2. Restoring File Shares
          6. Restoring Settings in Standard Edition Server Environments
            1. Step 1: Prepare for Restoration of Settings
            2. Step 2: Restore Settings
            3. Step 3: Start Services
            4. Step 4: Validate Services
            5. Next Steps
          7. Restoring Settings in Enterprise Pool Configurations
            1. Step 1: Prepare for Restoration of Settings
            2. Step 2: Restore Settings
            3. Step 3: Activate Servers (Only with a Re-created Enterprise Pool)
            4. Step 4: Start Services
            5. Step 5: Validate Server and Pool Functionality
            6. Next Steps
          8. Re-creating Enterprise Pools
          9. Reassigning Users
          10. Restoring Domain Information
          11. Restoring Sites
            1. Step 1: Determine the Recovery Support to Be Provided by the Secondary Site
            2. Step 2: Create a Deployment Plan and Restoration Strategy for the Secondary Site
            3. Step 3: Set Up the Secondary Site
            4. Step 4: Prepare the Primary Site to Support Recovery at the Secondary Site
            5. Step 5: Maintain the Secondary Site
            6. Step 6: Validate Site Recovery Capabilities by Simulating an Outage
            7. Step 7: Bring the Secondary Site Online
            8. Step 8: Restore the Primary Site and Bring It Back Online
        3. Summary
        4. Additional Resources
          1. On the Companion CD
    8. V. Technical Troubleshooting and Diagnostics
      1. 15. Administration
        1. Configuring Global Settings
          1. Configuring UC-specific Settings
          2. Configuring Policy-Specific Settings
          3. Configuring Service Connection Point Settings
          4. Configuring Trusted Server Settings
          5. Configuring User-Specific Settings
        2. Configuring Pool Settings
        3. Configuring Server Settings
          1. Configuring Settings for All Servers
          2. Configuring Diagnostic Settings
          3. Configuring Settings for Standard Edition and Enterprise Edition Servers
          4. Configuring Application Server Settings
          5. Configuring Filter Settings
          6. Configuring Logging Settings
          7. Configuring Conferencing Server Settings
          8. Configuring Communicator Web Access Server Settings
          9. Configuring Mediation Server Settings
          10. Configuring Edge Server Settings
          11. Configuring Federation Settings
        4. Migrating Users from Live Communications Server 2005 SP1 to Office Communications Server 2007
        5. Summary
        6. Additional Resources
          1. On the Companion CD
      2. 16. Diagnostic Tools and Resources
        1. Overview of Diagnostic Tools
        2. Using Server Setup Logs
        3. Using Event Logs
          1. Understanding Communicator Events
            1. Example of an Expected Event
            2. Examples of Problem Events and Troubleshooting Steps
          2. Understanding Server Events
            1. Examples of Normal Events
            2. Examples of Problem Events and Troubleshooting Steps
        4. Using Client and Server Trace Logs
          1. Understanding Office Communicator Traces
            1. Configuring Trace Settings
            2. Looking at Trace Files
          2. Understanding Office Communications Server Traces
            1. Example of Gathering a Server Trace
            2. Using Snooper
        5. Summary
        6. Additional Resources
          1. On the Companion CD
      3. 17. Troubleshooting Problem Scenarios
        1. Overview of the Troubleshooting Process
          1. Identifying Primary Problem Spaces by Technical Area
          2. Summary of Troubleshooting Steps
        2. Resolving Common Problem Scenarios
          1. Resolving Local and Remote Login Problems and Basic Operational Problems
            1. Examples of Resolving Common Office Communicator Problems
            2. Examples of Resolving Common Communicator Web Access Problems
          2. Resolving Conferencing Problems Involving Sharing Files and A/V
            1. Examples of Resolving Common Conferencing Problems
          3. Resolving Management and Configuration Problems
            1. Examples of Resolving Common Management and Configuration Problems
          4. Resolving Telephony Problems
            1. Examples of Resolving Common Telephony Problems
        3. Summary
        4. Additional Resources
          1. On the Companion CD
    9. VI. Technical Reference
      1. 18. Office Communications Server 2007 Fundamentals
        1. Understanding Session Initiation Protocol
          1. How Office Communications Server 2007 and Office Communicator 2007 Use SIP
          2. Common SIP Verbs
            1. REGISTER
            2. SUBSCRIBE and NOTIFY Requests
            3. SERVICE
            4. INVITE and MESSAGES
            5. ACK
            6. CANCEL
            7. BYE
          3. Common SIP Responses
            1. Informational
            2. Success
            3. Redirection
            4. Client Error
            5. Server Error
            6. Global Failure
        2. Understanding SIP Routing
          1. Overview of SIP Routing Concepts
            1. Record-Route Headers
            2. Route Headers
            3. Via Headers
            4. Contact Headers
            5. Route Signatures
        3. Understanding the Globally Routable User Agent URI
          1. Understanding GRUU Creation
          2. How the GRUU Is Used by Office Communications Server
        4. Understanding Enhanced Presence
          1. How Enhanced Presence Works
            1. Understanding Categories of Presence Information
            2. Understanding Containers of Presence Information
            3. Examples of Enhanced Presence
        5. Understanding Authentication in Office Communications Server 2007
          1. Using TLS and Certificates
          2. Overview of TLS
            1. Example of a TLS Handshake over the Network
          3. Overview of NTLM and Kerberos
          4. Troubleshooting Sign-in Problems
          5. Enabling NTLM v2
        6. Security Features of Office Communications Server 2007
          1. Federation Domain Validation
          2. Remote User Access
          3. Managing Access Rights
          4. Allowing URLs and File Transfers
          5. TLS and MTLS for Client and Server Message Integrity
        7. Summary
        8. Additional Resources
          1. Related Information
          2. On the Companion CD
      2. 19. Microsoft Office Communications Server 2007 Internals
        1. Understanding the Office Communications Server 2007 Architecture
          1. Understanding Pool Configurations
            1. Examining the Standard Edition Configuration
            2. Examining the Enterprise Edition: Consolidated Configuration
            3. Examining the Enterprise Edition: Expanded Configuration
          2. Understanding Enterprise Pools
        2. Understanding Office Communications Server 2007 Internal Components
          1. Examining Core Components
            1. Examining the RTCsrv.exe Process
            2. Examining the RTChost.exe Process
          2. Examining Presence Components
          3. Examining Conferencing Components
            1. Understanding the Focus
            2. Understanding the Focus Factory
            3. Understanding the Conferencing Server Factory
            4. Understanding the Conferencing Database
          4. Examining VoIP Components
            1. Understanding the Translation Service
            2. Understanding the Inbound Routing Component
            3. Understanding the Outbound Routing Component
        3. Summary
        4. Additional Resources
          1. On the Companion CD
    10. A. System Requirements
      1. System Requirements for Resource Kit Tools and Reference Material
        1. System Requirements for Resource Kit Tools and Reference Material
    11. Index
18.227.81.153