Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. PACKET PROCESSING 48 NETWORK PROCESSORS TDM-multiplexed voice channels. This only exacerbates the need for flexibility and upgradeability in network switching equipment, something the network processors are ideally suited to handle. It is assumed that the reader has a basic background on traditional PSTN-type telephony-inspired link platforms known as T1 and T3 (in North America) and E1 and E3 in Europe. These platforms allow transmission based on several protocols such as voice over TDM, frame relay, IP, and Table 3.1 summarizes the bandwidths of the more recent SONET-based links in the WAN. THE TIMING OF THE NETWORK-PROCESSING EVOLUTION As of the late spring of 2003, the accepted state-of-the-art speed in deployed network processing is OC-192 although there are devices that are able to function in OC-768 links; therefore, much of our attention will be focused on chips and architectures functioning at that speed. However, network equipment designers are already extremely anxious about the scalability of their architectures and designs in relation to the next logical performance step of OC-768. This step requires processors capa- ble of processing traffic at 40 Gbps wire speed. We will discuss some of the issues and trade-offs architects will sooner or later have to confront. The economic downturn following the stock market collapse in 2001 and the general slowdown that resulted following the tragic events on September 11, 2001, have also significantly delayed numerous investment plans and deployment schedules for 10 and 40 Gbps projects. The naturally induced financial conservatism has consequently affected the rate of market adoption for many of these new technologies. For the next couple of years, the main empha- sis of the network-processor market will most likely be in the OC-48 and multiple Gigabit Ethernet realms. The result has been mixed. On one hand, it has been negative for some vendors of cutting-edge 