Asymmetric Routing Topology; Asymmetric Routing And Other Service Control Capabilities - Cisco SCE8000 GBE Installation And Configuration Manual

Chapter 3 Cisco SCE8000 GBE Topology and Topology-Related Parameters

Asymmetric Routing Topology

In some Service Control deployments, asymmetrical routing occurs between potential service control
insertion points. Asymmetrical routing can cause a situation in which the two directions of a
bi-directional flow pass through different SCE platforms, resulting in each SCE platform seeing only one
direction of the flow (either the inbound traffic or the outbound traffic).
This problem is typically solved by connecting the two SCE platforms in cascade mode, thereby making
sure that both directions of a flow run through the same SCE platform. However, this is sometimes not
feasible, due to the fact that the SCE platforms sharing the split flow are geographically remote
(especially common upon peering insertion). In this type of scenario, the asymmetric routing solution
enables the SCE platform to handle such traffic, allowing SCA BB to classify traffic based on a single
direction and to apply basic reporting and global control features to uni-directional traffic.

Asymmetric Routing and Other Service Control Capabilities

Asymmetric routing can be combined with most other Service Control capabilities, however there are
some exceptions.
Service Control capabilities that cannot be used in an asymmetric routing topology include the
following:
•
•
•
OL-19897-02
Subscriber redirect
Subscriber notification
Any kind of subscriber integration. (Use subscriber-less mode or anonymous subscriber mode
instead)
Cisco SCE8000 GBE Installation and Configuration Guide
Asymmetric Routing Topology
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