Network Processor based Exchange Terminal : Implementation and evaluation

Abstract: When communication nodes are connected to different networks, different kinds of Exchange Terminals (ETs) i.e., line card, are used. The different media we consider here have a bit rate between 1.5Mbps to 622Mbps and use protocols such as ATM or IP. In order to minimize the number of different types of ET boards, it is interesting to study the possibility of using Network Processors (NP) to build a generic ET that is able to handle several link layer and network layer protocols and operate at a wide variety of bit rates. This report investigates the potential of implementing an ET board using a one-chip or twochip solution using an Intel Network Processor (NP). The design is described in detail including a performance analysis of the different modules (microblocks) used. The report also provides an evaluation of the IXP2400 network processor and contrasts it to some other network processors. The detailed performance evaluation is based on a simulator of the IXP2400, which is part of Intel's Software Development Kit (SDK) version 3.0. In addition, I have investigated: the memory bus bandwidth, memory access latencies, and compared Ccompiler against hand-written microcode. These tests were based on using an application for this ET board, which I have implemented. It proved to be difficult to fit all the required functions into a single chip solution. The result is either one must wait for the next generation of this chip or one has to use a two-chip solution. In addition, the software development environment used in the project was only a pre-release, and not all services worked as promised. However, a clear result is that implementing an ET board, supporting the commonly desired functions, using a Network Processor is both feasible and straightforward.