TABLE OF CONTENTS 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 players in this emerging and specialized network-processing industry branch.
Originally, and to a large extent today still, the vast majority of storage devices used by computer systems 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 such as the Small Computer System Interface (SCSI) bus. Its high data transfer rate, low latency, and reliability account for its wide-scale success in coupling computers with a plethora of storage devices.
Magnetic disks are the primary online storage medium. Tapes are considered more...
