Prerequisites For Redirecting Isg Subscriber Traffic; Restrictions For Redirecting Isg Subscriber Traffic; Redirecting Isg Subscriber Traffic; Isg Layer 4 Redirect Overview - Cisco 10000 Series Configuration Manual

Prerequisites for Redirecting ISG Subscriber Traffic

Prerequisites for Redirecting ISG Subscriber Traffic
For information about release and platform support, see the
Subscriber Traffic" section on page

Restrictions for Redirecting ISG Subscriber Traffic

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Redirecting ISG Subscriber Traffic

Before you configure Layer 4 Redirect, you should understand the following concepts:
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ISG Layer 4 Redirect Overview

The ISG Layer 4 Redirect feature redirects specified packets to servers that manage the packets in a
specified manner. For example, packets sent upstream by unauthorized users can be forwarded to a server
that redirects the users to a logon page. Similarly, if users try to access a service to which they have not
logged on, the packets can be redirected to a server that provides a service logon screen.
The Layer 4 Redirect feature supports three types of redirection, which can be applied to subscriber
sessions or to flows:
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A redirect server can be any server that is programmed to respond to the redirected packets. If ISG is
used with a web portal, unauthenticated subscribers can be sent automatically to a logon page when they
start a browser session. Web portal applications can also redirect to service logon pages, advertising
pages, and message pages.
Redirected packets are sent to an individual redirect server or redirect server group that consists of one
or more servers. ISG selects one server from the group in a rotating fashion to receive the redirected
packets.
Cisco 10000 Series Router Access Network Control Protocol Configuration Guide
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Chapter 4
The ISG Layer 4 Redirect feature applies only to TCP or UDP traffic.
If a valid CLI configured ISG service is forwarded through COA to a new session and fails (ISG
service is unable to find an accounting list):
BRAS does not wait for the hardware to be provisioned
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An ACK message is relayed
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ISG services are not applied, and
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Tracebacks are observed
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ISG Layer 4 Redirect Overview, page 4-2
Layer 4 Redirect Applications, page 4-3
Permanent redirection—Specified traffic is redirected to the specified server all the time.
Initial redirection—Specified traffic is redirected for a specific duration of the time only, starting
from when the feature is applied.
Periodic redirection—Specified traffic is periodically redirected. The traffic is redirected for a
specified duration of time. The redirection is then suspended for another specified duration. This
cycle is repeated.
Redirecting Subscriber Traffic Using Intelligent Service Gateway Layer 4 Redirect
"Feature Information for Redirecting ISG
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