Cisco IOS Intelligent Service Gateway Configuration Guide, Release 12.2 SB - Configuring ISG Network Forwarding Policies [Cisco IOS Software Releases 12.2 SB]

Table Of Contents

Configuring ISG Network Forwarding Policies

Contents

Prerequisites for Configuring ISG Network Forwarding Policies

Restrictions for Configuring ISG Network Forwarding Policies

Information About ISG Network Policies

Network Policies

Configuration Sources for Network Policies

How to Configure ISG Network Policies

Configuring Network Policies for PPP Sessions in Service Policy Maps

Prerequisites

What to Do Next

Configuring Network Policies for IP Sessions in Service Policy Maps

What to Do Next

Configuration Examples for ISG Network Policies

Network Forwarding Policy for PPP Sessions: Example

Network Forwarding Policy for IP Sessions: Example

Additional References

Related Documents

Technical Assistance

Feature Information for ISG Network Policies

Configuring ISG Network Forwarding Policies

First Published: March 20, 2006

Last Updated: March 20, 2006

Intelligent Service Gateway (ISG) is a Cisco IOS software feature set that provides a structured framework in which edge devices can deliver flexible and scalable services to subscribers. An ISG network forwarding policy is a type of traffic policy that allows packets to be routed or forwarded to and from an upstream network. This module provides information about how to configure network forwarding policies.

Finding Feature Information in This Module

Your Cisco IOS software release may not support all features. To find information about feature support and configuration and platform requirements, use the "Feature Information for ISG Network Policies" section.

Contents

•Prerequisites for Configuring ISG Network Forwarding Policies

•Restrictions for Configuring ISG Network Forwarding Policies

•Information About ISG Network Policies

•How to Configure ISG Network Policies

•Configuration Examples for ISG Network Policies

•Additional References

•Feature Information for ISG Network Policies

Prerequisites for Configuring ISG Network Forwarding Policies

For information about release and platform support, see the "Feature Information for ISG Network Policies" section.

Restrictions for Configuring ISG Network Forwarding Policies

A service can contain only one network forwarding policy.

For each subscriber session, only one instance of a network forwarding policy can be in effect at any one time.

Information About ISG Network Policies

Before you configure network forwarding policies, you should understand the following concepts:

•Network Policies

•Configuration Sources for Network Policies

Network Policies

For subscriber packets to reach a network, some form of forwarding must be specified for a subscriber session. A traffic policy that allows packets to be routed or forwarded to and from an upstream network is known as a network forwarding policy.

Where the network forwarding policy type is routing, forwarding decisions are made at Layer 3, and a VRF (Virtual Routing and Forwarding) identifier must be specified to indicate which routing table should be used to make the routing decision (each VRF represents an independent routing context within a single router). Where the network policy type is forwarding, forwarding decisions are made at Layer 2, which means that all subscriber packets are forwarded to and from a single virtual endpoint within the system. This virtual endpoint represents a Layer 2 tunnel, and a tunnel identifier determines which tunnel should be used. If a network forwarding policy is not specified, the global routing table will be used to route traffic.

An ISG service that includes a network forwarding policy is known as a primary service. Primary services are mutually exclusive and may not be active simultaneously. Upon activation of a new primary service, ISG will deactivate the existing primary service and any other services dependent on the existing primary service through association with a service group.

Configuration Sources for Network Policies

Network policies can be configured in user profiles and service profiles on an external authentication, authorization, and accounting (AAA) server or in service policy maps on the ISG-enabled device. A network forwarding policy configured in a user profile takes precedence over a network forwarding policy specified in a service. If a network forwarding policy is not specified in a user profile or service, the ISG session will inherit the network service from another source. ISG can inherit a network service from the following sources:

•Global

•Interface

•Subinterface

•Virtual template

•Virtual circuit (VC) class

•Permanent virtual circuit (PVC)

These configuration sources are listed in order of precedence. For example, a network forwarding policy that is configured for a virtual template takes precedence over a network forwarding policy that is configured on an interface.

For each subscriber session, only one instance of a network forwarding policy can be in effect at any point in time.

How to Configure ISG Network Policies

This section contains the following tasks:

•Configuring Network Policies for PPP Sessions in Service Policy Maps

•Configuring Network Policies for IP Sessions in Service Policy Maps

Configuring Network Policies for PPP Sessions in Service Policy Maps

Network policies can be configured in user profiles or service profiles on an external AAA server or in a service policy map on the ISG device. Perform this task to configure a network forwarding policy for PPP session in a service policy map on the ISG device.

Note If a network forwarding policy is not specified in a user profile, service profile, or service policy map, a subscriber session will inherit the network forwarding policy from another source. See the "Configuration Sources for Network Policies" section for more information.

Prerequisites

This task assumes that virtual private dial-up network (VPDN) groups have been configured.

SUMMARY STEPS

1. enable

2. configure terminal

3. policy-map type service policy-map-name

4. service vpdn group vpdn-group-name

or

service local

or

service relay pppoe vpdn group vpdn-group-name

5. ip vrf forwarding name-of-vrf

DETAILED STEPS
Command or Action

Purpose

Step 1

enable
Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2

configure terminal
Example:

Router# configure terminal

Enters global configuration mode.

Step 3

policy-map type service policy-map-name
Example:

Router(config)# policy-map type service service1

Creates or modifies a service policy map, which is used to define an ISG service.
Step 4
service vpdn group vpdn-group-name
or

service local
or

service relay pppoe vpdn group vpdn-group-name
Example:

Router(config-service-policymap)# service vpdn group vpdn1
Example:

Router(config-service-policymap)# service local
Example:

Router(config-service-policymap)# service relay pppoe vpdn group vpdn1
Provides virtual private dialup network (VPDN) service.

or

Provides local termination service.

or

Provides VPDN service by relaying PPPoE over VPDN L2TP tunnels.

•If you terminate the service locally by configuring the service local command, you can also specify the routing domain in which to terminate the session by configuring the ip vrf forwarding command.
Step 5

ip vrf forwarding name-of-vrf
Example:

Router(config-service-policymap)# ip vrf forwarding blue

Associates the service with a VRF.

•Perform this step only if you configured the service local command in Step 4. If you configured the service local command, you can use the ip vrf forwarding command to specify the routing domain in which to terminate session. If you do not specify the routing domain, the global VRF will be used.
What to Do Next

You may want to configure a method of activating the service policy map; for example, control policies can be used to activate services. For more information about methods of service activation, see the module "Configuring ISG Subscriber Services."

Configuring Network Policies for IP Sessions in Service Policy Maps

Network policies can be configured in user profiles or service profiles on an external AAA server or in a service policy map on the ISG device. Perform this task to configure a network forwarding policy for IP sessions in a service policy map on the device.

Note If a network forwarding policy is not specified in a user profile, service profile, or service policy map, a subscriber session will inherit the network forwarding policy from another source. See the "Configuration Sources for Network Policies" section for more information.

SUMMARY STEPS

1. enable

2. configure terminal

3. policy-map type service policy-map-name

4. ip vrf forwarding name-of-vrf

5. sg-service-type primary

DETAILED STEPS

Command or Action

Purpose

Step 1

enable
Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2

configure terminal
Example:

Router# configure terminal

Enters global configuration mode.

Step 3

policy-map type service policy-map-name
Example:

Router(config)# policy-map type service service1

Creates or modifies a service policy map, which is used to define an ISG service.

Step 4

ip vrf forwarding name-of-vrf
Example:

Router(config-service-policymap)# ip vrf forwarding blue

Associates the service with a VRF.

Step 5

sg-service-type primary
Example:

Router(config-service-policymap)# sg-service-type primary

Defines the service as a primary.

•A primary service is a service that contains a network forwarding policy. A primary service must be defined as a primary service by using the sg-service-type primary command. Any service that is not a primary service is defined as a secondary service by default.

What to Do Next

You may want to configure a method of activating the service policy map; for example, control policies can be used to activate services. For more information about methods of service activation, see the module "Configuring ISG Subscriber Services."

Configuration Examples for ISG Network Policies

This section contains the following examples:

•Network Forwarding Policy for PPP Sessions: Example

•Network Forwarding Policy for IP Sessions: Example

Network Forwarding Policy for PPP Sessions: Example

The following example shows a service policy map configured with a network forwarding policy for PPP sessions:
policy-map type service my_service
 service vpdn group vpdn1
Network Forwarding Policy for IP Sessions: Example

The following example shows a service policy map configured with a network forwarding policy for IP sessions:
policy-map type service my_service
 ip vrf forwarding vrf1
Additional References

The following sections provide references related to ISG network forwarding policies.

Related Documents

Related Topic

Document Title

ISG commands

Cisco IOS Intelligent Service Gateway Command Reference

PPP and VPDN configuration tasks

Cisco IOS Dial Services Configuration Guide, Release 12.2

PPP and VPDN commands

Cisco IOS Dial Services Command Reference, Release 12.2

Technical Assistance

Description

Link

Technical Assistance Center (TAC) home page, containing 30,000 pages of searchable technical content, including links to products, technologies, solutions, technical tips, and tools. Registered Cisco.com users can log in from this page to access even more content.

http://www.cisco.com/public/support/tac/home.shtml

Feature Information for ISG Network Policies

Table 14 lists the features in this module and provides links to specific configuration information. Only features that were introduced or modified in Cisco IOS Release 12.2(28)SB or later releases appear in the table. If you are looking for information on a feature in this technology that is not documented here, see the "Intelligent Service Gateway Features Roadmap."

Not all commands may be available in your Cisco IOS software release. For details on when support for specific commands was introduced, see the command reference documents.

Cisco IOS software images are specific to a Cisco IOS software release, a feature set, and a platform. Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at the login dialog box and follow the instructions that appear.

Note Table 14 list only the Cisco IOS software release that introduced support for a given feature in a given Cisco IOS software release train. Unless noted otherwise, subsequent releases of that Cisco IOS software release train also support that feature.

Table 14 Feature Information for ISG Network Forwarding Policies

Feature Name

Releases

Feature Configuration Information

ISG: Network Interface: IP Routed, VRF-Aware MPLS

12.2(28)SB

ISG supports multiple forwarding types to connect sessions to networks. These connections can be to Internet, corporate Intranets, ISPs, or walled gardens for content delivery. ISG supports both routed and MPLS-enabled interfaces for network access.

The following sections provide information about this feature:

•Information About ISG Network Policies

•How to Configure ISG Network Policies

ISG: Network Interface: Tunneled (L2TP)

12.2(28)SB

ISG is flexible to support multiple interface types to connect sessions to networks. These connections can be to Internet, corporate Intranets, ISPs or walled gardens for content delivery. ISG supports tunneled interfaces to networks.

The following sections provide information about this feature:

•Information About ISG Network Policies

•How to Configure ISG Network Policies

Copyright © 2006 Cisco Systems, Inc. All rights reserved.