Summary

This chapter provides in-depth analysis of the physical layer and data-link layer technologies employed by the SPI, Ethernet, and FC. Many of the details provided are ancillaries to design and troubleshooting efforts rather than daily network operation. That said, a thorough understanding of the details provided can enable network administrators to optimize their daily operations.

Though the SPI is waning in popularity, it is still important to understand that the capabilities and limitations of the SPI influenced the evolution of SCSI performance requirements that must now be met by modern storage networks built on Ethernet or FC. For this reason, the SPI is included in this chapter. Insight to the functional capabilities of Ethernet and FC relative to each other is provided to enable readers to properly employ the use of each technology based on application requirements. Readers should remember that Ethernet is deployed in conjunction with TCP/IP to provide a complete solution. So, the limitations of Ethernet presented in this chapter should not be construed as barriers to deployment. Likewise, many of the capabilities of FC are not examined in this chapter. The subsequent chapters of Part II, "OSI Layers," build upon this chapter to provide a complete picture of each solution.