Cisco DS-C9216I-K9 Configuration Manual page 306

Configuring FCIP
Figure 24-11
FC
B ports bridge Fibre Channel traffic from one E port to a remote E port without participating in
fabric-related activities such as principal switch election, Domain ID assignment, and Fibre Channel
routing (FSPF). For example, Class F traffic entering a SAN extender does not interact with the B port.
The traffic is transparently propagated (bridged) over a WAN interface before exiting the remote B port.
This bridge results in both E ports exchanging Class F information which ultimately leads to normal ISL
behavior such as fabric merging and routing.
FCIP links between B port SAN extenders do not exchange the same information as FCIP links between
E ports, and are therefore incompatible. This is reflected by the terminology used in FC-BB-2: while VE
ports establish a virtual ISL over a FCIP link, B ports use a B access ISL.
Cisco MDS 9000 Fabric Manager Switch Configuration Guide
24-18
FCIP B Port and Fibre Channel E Port
Switch A
FC
F
FC
F
F
FC
Switch B
FC
E
F
FC
Switch A
FC
F
F
FC bridge
E
FC
FC B
access
Switch B
FC
E
F
FC
E port
IP
FCIP link
VE GE
Virtual ISL
B port
FCIP link
B
B access ISL
E FC
ISL
Chapter 24 Configuring IP Storage
Switch C
GE VE
FC bridge
B FC
B
access
Switch C
IP
FC
E
ISL
FC
F
E
FC
FC
F
E
FC
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