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Cisco IOS Dial TechnologiesConfiguration Guide
© 2001–2009 Cisco Systems, Inc. All rights reserved.
iii
CONTENTS
About Cisco IOS and Cisco IOS XE Software Documentation lv
Documentation Objectives lv
Audience lv
Documentation Conventions lvi
Typographic Conventions lvi
Command Syntax Conventions lvi
Software Conventions lvii
Reader Alert Conventions lvii
Documentation Organization lvii
Cisco IOS Documentation Set lviii
Cisco IOS Documentation on Cisco.com lviii
Configuration Guides, Command References, and Supplementary Resources lix
Additional Resources and Documentation Feedback lxv
Using the Command-Line Interface in Cisco IOS and Cisco IOS XE Software lxvii
Initially Configuring a Device lxvii
Using the CLI lxviii
Understanding Command Modes lxviii
Using the Interactive Help Feature lxxi
Understanding Command Syntax lxxii
Understanding Enable and Enable Secret Passwords lxxiv
Using the Command History Feature lxxiv
Abbreviating Commands lxxv
Using Aliases for CLI Commands lxxv
Using the no and default Forms of Commands lxxvi
Using the debug Command lxxvi
Filtering Output Using Output Modifiers lxxvi
Understanding CLI Error Messages lxxvii
Saving Changes to a Configuration lxxviii
Additional Information lxxviii
Overview of Dial Interfaces, Controllers, and Lines 83
Cisco IOS Dial Components 83
Logical Constructs 85
Asynchronous Interfaces 85
Contents
iv
Group Asynchronous Interfaces 86
Virtual Template Interfaces 86
Templates for Virtual Access Interfaces 87
Templates for Protocol Translation 87
Logical Interfaces 87
Dialer Interfaces 88
Virtual Access Interfaces 89
Virtual Asynchronous Interfaces 90
Circuit-Switched Digital Calls 90
T1 and E1 Controllers 91
Non-ISDN Channelized T1 and Channelized E1 Lines 91
ISDN Service 92
ISDN BRI 93
ISDN PRI 93
Line Types 94
Relationship Between Lines and Interfaces 96
Asynchronous Interfaces and Physical Terminal Lines 96
Synchronous Interfaces and Virtual Terminal Lines 97
Encapsulation Types 98
Configuring Asynchronous Lines and Interfaces 99
How to Configure Asynchronous Interfaces and Lines 99
Configuring a Typical Asynchronous Interface 99
Monitoring and Maintaining Asynchronous Connections 100
Creating a Group Asynchronous Interface 101
Verifying the Group Interface Configuration 102
Configuring Asynchronous Rotary Line Queueing 105
Verifying Asynchronous Rotary Line Queueing 106
Troubleshooting Asynchronous Rotary Lines 106
Monitoring and Maintaining Asynchronous Rotary Line Queues 106
Configuring Autoselect 107
Verifying Autoselect PPP 108
Verifying Autoselect ARA 108
How to Configure Other Asynchronous Line and Interface Features 109
Configuring the Auxiliary (AUX) Port 109
Establishing and Controlling the EXEC Process 110
Enabling Routing on Asynchronous Interfaces 111
Configuring Dedicated or Interactive PPP and SLIP Sessions 111
Conserving Network Addresses 112
Contents
v
Using Advanced Addressing Methods for Remote Devices 113
Assigning a Default Asynchronous Address 113
Allowing an Asynchronous Address to Be Assigned Dynamically 113
Optimizing Available Bandwidth 114
Configuring Header Compression 114
Forcing Header Compression at the EXEC Level 114
Configuration Examples for Asynchronous Interfaces and Lines 115
Interface and Line Configuration Examples 115
Asynchronous Interface Backup DDR Configuration Example 116
Passive Header Compression and Default Address Example 116
High-Density Dial-In Solution Using Autoselect and EXEC Control Example 116
Asynchronous Line Backup DDR Configuration Example 116
Line AUX Configuration Example 117
Rotary Group Examples 117
Dedicated Asynchronous Interface Configuration Example 118
Access Restriction on the Asynchronous Interface Example 118
Group and Member Asynchronous Interface Examples 118
Asynchronous Group Interface Examples 118
Modem Asynchronous Group Example 119
High-Density Dial-In Solution Using an Asynchronous Group 119
Asynchronous Interface Address Pool Examples 120
DHCP Pooling Example 120
Local Pooling Example 120
Configuring Specific IP Addresses for an Interface 121
IP and SLIP Using an Asynchronous Interface Example 121
IP and PPP Asynchronous Interface Configuration Example 121
Asynchronous Routing and Dynamic Addressing Configuration Example 121
TCP Header Compression Configuration Example 122
Network Address Conservation Using the ip unnumbered Command Example 122
Asynchronous Interface As the Only Network Interface Example 122
Routing on a Dedicated Dial-In Router Example 123
IGRP Configuration Example 123
Asynchronous Call Queueing by Role 125
Finding Feature Information 125
Contents 125
Prerequisites for Asynchronous Call Queueing by Role 126
Restrictions for Asynchronous Call Queueing by Role 126
Information About Asynchronous Call Queueing by Role 126
