Solutions in this chapter:

• The Architecture of SANs

• Fibre Channel Protocol Basics

• Classes of Service

• Storage Network Topologies

• Fabric Services

• Summary

• Solutions Fast Track

• Frequently Asked Questions

Introduction

Storage Area Network (SAN) infrastructures are built using new technologies that, although related to and derived from other technologies such as SCSI and IP networking, has its own set of terminology and concepts. Like standard computer system networking, Fibre Channel also has its own stack of protocol levels, ranging from the physical connectors and media (FC-0) to upper-level protocols (FC-4). Each of these levels defines a different and separate part of how Fibre Channel equipment communicates. An understanding of these protocol levels, although not required, helps in understanding the equipment and how to debug and monitor the equipment. The different FC-4 protocols (FCP, IP, Virtual Interface [VI], and others) are tied directly to the different kinds of applications (storage, networking, and clustering), and enable Fibre Channel to support a robust set of uses.

This chapter introduces some of the basics of Fibre Channel and reviews the underlying architecture of Storage Area Networks (SANs). You will discover the major parts of the Fibre Channel protocol, the primary physical components involved, and how they relate to the software and applications running on a SAN. At the end of this chapter you will be able to determine the kinds of protocols you need to run in your network, and better understand the various SAN topologies and terminology.

The Architecture of SANs

SANs provide a topology...