Unlike Fibre Channel over IPIFCP lets users maintain the Fibre Channel architecture while gaining the benefits of IP networks.
IFCP wraps Fibre Channel data in IP packets but maps IP addresses to individual Fibre Channel devices. That provides more stability than a tunneled FCIP deployment, some vendors say.
When iFCP creates the IP packets, it inserts information that is readable by network devices and routable within the IP network. "IFCP gives you visibility into the talking pairs between servers and storage, and gives you a way to monitor discrete conversations between storage initiators and targets," says Tom Clark, director of technical marketing at Nishan, which supports iFCP, FCIP and iSCSI in its storage products.
Because the packets contain IP addresses, customers can use IP network management tools such as HP's OpenView to manage the flow of Fibre Channel data using iFCP.
Fibre Channel over IP (FCIP or FC/IP, also known as Fibre Channel tunneling or storage tunneling), is an Internet Protocol (IP)-based storage networking technology developed by the Internet Engineering Task Force (IETF) and defined in RFC 3821. FCIP mechanisms enable the transmission of Fibre Channel (FC) information by tunneling data between storage area network (SAN) facilities over IP networks; this capacity facilitates data sharing over a geographically distributed enterprise. One of two main approaches to storage data transmission over IP networks, FCIP is among the key technologies expected to help bring about rapid development of the storage area network market by increasing the capabilities and performance of storage data transmission.
iFCP and FCIP are intended for interconnecting storage area network (SAN) devices to support data movement and in the case of iFCP also provide SAN fabric segmentation which is a form of routing. iFCP supports movement and routing of data across different SAN segments where FCIP creates a tunnel between two sites in what ends up being a single fabric or segment unless a segment router is used. What the three (iSCSI, iFCP, FCIP) have in common is IP as a network transport protocol for moving block data over IP based networks.
There has debate of the pros and cons between when and where to use iFCP vs. FCIP and which is better. Most vendors support FCIP, while McData, via acquisitions of Nishan (iFCP) and CNT (FCIP), supports both. One thing to keep in mind is that even though different vendors support FCIP, I'm not aware of any vendor supporting an FCIP-based product that communicates with other vendors' FCIP-based product. Learn more about the differences, characteristics and when to use iSCSI, iFCP and FCIP in Chapter 4: "Storage and I/O networks" and Chapter 5: "Metropolitan and wide area storage networks" in my book "Resilient Storage Networks" (Elsevier) as well as in the SearchStorage tip "Bridging the gap".