ING NETWORK PROCESSORS: STORAGE PROCESSORS, CLASSIFICATION PROCESSORS, SEARCH ENGINES, SWITCH FABRICS, AND TRAFFIC MANAGERS Downloaded 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. PERIPHERAL CHIPS SUPPORTING NETWORK PROCESSORS: STORAGE PROCESSORS Downloaded 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 11 STORAGE NETWORK PROCESSORS (SNPS) In this chapter, we discuss the influence of the evolution of storage networks on network processing and show how the storage network requirements create the demand for a breed of highly specialized processors that go beyond mainstream network processors. These storage network processors (SNPs) must be able to handle very high-speed data traffic while performing their tasks under much more stringent jitter and latency performance requirements than ordinary network processors. We discuss the various industry associations that are in the process of resolving the conflicts of interests among multiple technologies and vendors. We also review the approaches taken by a couple of major play- ers in this emerging and specialized network-processing industry branch. STORAGE NETWORK PROCESSING: THE CONTEXT Originally, and to a large extent today still, the vast majority of storage devices used by computer sys- tems were attached physically and directly onto the computer system they were supposed to serve. One would talk about directly attached storage (DAS) devices. Although this is a simple concept to grasp, it is obviously a limiting factor as a user must have access to the specific server on which the storage units are connected in order to access the stored data. DAS devices usually interface through standard interconnects suc