Overview of Traffic Mirroring

Traffic mirroring allows you to intercept subscriber traffic by configuring a service with the SRC software that applies policies on a JUNOS routing platform in a fashion similar to the application of firewall filters.

When the SAE activates a traffic-mirroring service session, the session applies filters to the forwarding table to mirror traffic using the preconfigured mirroring port and policy-specified filters. The process is similar to service activation on interfaces, but this service is activated on the forwarding table for a JUNOS routing platform and is applicable only to input.

By activating traffic-mirroring services in an SRC-managed environment, service providers can use the SRC software to simplify traffic mirroring on their network equipment. The SRC software can set up a policy to:

• Monitor subscriber traffic and intercept traffic from a particular source or to a particular destination.
• Take actions for subscribers with intercepted traffic by applying policies to the subscriber traffic.

You must deploy traffic mirroring on JUNOS routing platforms to monitor the subscriber traffic.

The traffic-mirroring application is not compatible with Web application server clusters; it should be run in a standalone Web application server.

Traffic-Mirroring Application

The SRC application library provides a traffic-mirroring application that can mirror subscriber traffic on any subscriber access platform supported by the SRC software. You set up traffic mirroring by configuring a service with the SRC software that applies policies on a JUNOS routing platform to mirror subscriber traffic in the SRC-managed network. The traffic-mirroring application provides robust sample data for mirroring traffic. Figure 1 illustrates a sample network configuration that contains JUNOSe routers and JUNOS routing platforms.

Figure 1: Sample Network Topology with a JUNOSe Router and JUNOS Routing Platforms

The implementation includes:

• Policies, services, router definitions, and SAE configuration in the sample data. Sample entries for traffic mirroring have the prefix TM.

  For information about installing sample data, see Installing the Sample SRC Applications.

• Sample policies and services to mirror subscriber traffic.
• Traffic Mirroring Administration portal.

You can use the sample data to create a demonstration implementation. The traffic-mirroring router definitions, identified as TM<routername> in the sample data, can be configured to act as simulated routers for the demonstration environment. For information about setting up a simulated router, see Configuring Simulated Router Drivers (SRC CLI).

You can also customize the sample data to use traffic mirroring in your network, or you can use the samples as a guide to create your own implementation.

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