Information Storage and Management: Storing, Managing, and Protecting Digital Information in Classic, Virtualized, and Cloud Environments, Second Edition

Chapter 6

IP SAN and FCoE

Key Concepts

iSCSI Protocol

Native and Bridged iSCSI

FCIP Protocol

FCoE Protocol

Traditional SAN enables the transfer of block I/O over Fibre Channel and provides high performance and scalability. These advantages of FC SAN come with the additional cost of buying FC components, such as FC HBA and switches. Organizations typically have an existing Internet Protocol (IP)-based infrastructure, which could be leveraged for storage networking. Advancements in technology have enabled IP to be used for transporting block I/O over the IP network. This technology of transporting block I/Os over an IP is referred to as IP SAN. IP is a mature technology, and using IP as a storage networking option provides several advantages. When block I/O is run over IP, the existing network infrastructure can be leveraged, which is more economical than investing in a new SAN infrastructure. In addition, many robust and mature security options are now available for IP networks. Many long-distance, disaster recovery (DR) solutions are already leveraging IP-based networks. With IP SAN, organizations can extend the geographical reach of their storage infrastructure.

Two primary protocols that leverage IP as the transport mechanism are Internet SCSI (iSCSI) and Fibre Channel over IP (FCIP). iSCSI is encapsulation of SCSI I/O over IP. FCIP is a protocol in which an FCIP entity such as an FCIP gateway is used to tunnel FC fabrics through an IP network. In FCIP, FC frames are encapsulated ...