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FIP provides a functionality for discovering and logging in to an FCF. After discovering and logging in, FIP allows FCoE traffic
to be sent and received between FCoE end-devices (ENodes) and the FCF. FIP uses its own EtherType and frame format. The
below illustration about FIP discovery, depicts the communication that occurs between an ENode server and an FCoE switch
(FCF).
FIP performs the following functions:
● FIP virtual local area network (VLAN) discovery: FCoE devices (Enodes) discover the FCoE VLANs on which to transmit and
receive FIP and FCoE traffic.
● FIP discovery: FCoE end-devices and FCFs are automatically discovered.
● Initialization: FCoE devices perform fabric login (FLOGI) and fabric discovery (FDISC) to create a virtual link with an FCoE
switch.
● Maintenance: A valid virtual link between an FCoE device and an FCoE switch is maintained and the link termination logout
(LOGO) functions properly.
Figure 43. FIP Discovery and Login between an ENode and an FCF
FIP Snooping on Ethernet Bridges
In a converged Ethernet network, intermediate Ethernet bridges can snoop on FIP packets during the login process on an FCF.
Then, using ACLs, a transit bridge can permit only authorized FCoE traffic to be transmitted between an FCoE end-device and
an FCF. An Ethernet bridge that provides these functions is called a FIP snooping bridge (FSB).
On a FIP snooping bridge, ACLs are created dynamically as FIP login frames are processed. The ACLs are installed on switch
ports configured for the following port modes:
● ENode mode for server-facing ports
● FCF mode for a trusted port directly connected to an FCF
FIP Snooping
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