wnloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Source: NETWORK PROCESSORS CHAPTER 7 AGERE PAYLOADPLUS R FAMILY OF NETWORK PROCESSORS Agere Systems is a recent spin-off from Lucent Technologies. It was formed after Lucent's acquisi- tion a couple of years ago of a network-processing startup with the same name and the actual busi- ness of the former Microelectronics Division of Lucent. Agere Systems is now one of the world leaders in the sale of communications semiconductors. The company designs, develops, and manu- factures integrated circuits for use in a broad range of communications and computer equipment. It recently announced its exit from the industry of optoelectronic components for communications net- works. Its full line of communications chips includes network processors, switch fabrics, framers, Synchronous Optical Network (SONET), Synchronous Digital Hierarchy (SDH), Plesiochronous Digital Hierarchy (PDH), high-speed physical-layer-related products, and even digital signal proces- sor (DSP) products. In this chapter, we will only be looking at the most advanced members of the company's PayloadPlus family of network processors in both the OC-48c and OC-192 realms. This product fam- ily is geared toward the implementation of intelligent communication equipment with processing capabilities that span layers 2 through 7. These products focus on the wire-speed data stream. They work in conjunction with physical interface devices, traditional lower-speed microprocessors, and backplane fabric offerings to provide a complete solution for networking and communication appli- cations. We will conclude our review of Agere's approach after also taking a brief look at other asso- ciated chips from Agere that provide the advantage of a complete systems solution. PAYLOADPLUS® ARCHITECTURE: THE BIG PICTURE Agere System's PayloadPlus is a comprehensi