Overview

Broadband access is a market segment where network processors play a significant role. Broadband access devices that use network processors for data-plane functions include integrated access devices, DSLAM line cards and trunk cards, and B-RAS aggregator devices. This chapter describes the design and implementation of a DSLAM line card application that meets the requirements for the next generation of intelligent DSLAM architectures, in which the line card offers Layer-2 and Layer-3 services using VLANs and IP routing. The DSLAM line card application is targeted to run on the Intel IXP2350 Network Processor using the 900/600 product SKU, and has been implemented using the Intel C Compiler in the autopartitioning mode.

The IP DSLAM case study shows you how to apply the various concepts discussed in the previous sections of the book. The case study focuses on presenting the important aspects of the application at a general level. Here you can find the functional and performance requirements, followed by the important design choices made in the implementation of this application, including the design of packet buffering, structuring of the data flow, the determination of packet-processing stages in the application pipeline, and the decomposition of each packet-processing stage into microblocks. A performance analysis of the application shows you the resulting headroom available in several dimensions. For detailed description of the application, you can refer to the autopartitioning mode example designs and microblocks in the reference manuals...