FCF mode—A switch operating in this mode is called an FCF switch. Its VFC interfaces support E
mode (E_Port) and F mode (F_Port).
NPV mode—A switch operating in this mode is called an N_Port Virtualization (NPV) switch. Its
VFC interfaces support F mode (F_Port) and NP mode (NP_Port).
An FCoE-capable switch can operate in the following modes:
FCF mode—When the switch operates in this mode, it can connect to the E_Port on another FCF
switch through its E_Port, or connect to the N_Port on a node or the NP_Port on an NPV switch
through its F_Port.
NPV mode—When the switch operates in this mode, it can connect to the N_Port on a node
through its F_Port or to the F_Port on an FCF switch through its NP_Port.
Non-FCoE mode—When the switch operates in this mode, it is a standard switch and does not
provide any FCoE capabilities.
An FCF switch encapsulates FC frames in Ethernet frames and uses FCoE virtual links to simulate physical
FC links. Therefore, it provides standard FC switching capabilities and features on a lossless Ethernet
Figure 10 FCF network diagram
In an FCoE environment as shown in
switch communicate over Ethernet interfaces on a lossless Ethernet network. The FCoE virtual link
between the ENode and FCF switch connects a VN interface to a VFC interface, and the FCoE virtual link
between FCF switches connects two VFC interfaces.
Each FCF switch is assigned a domain ID. Each FC SAN supports a maximum number of 239 domain IDs,
so an FC SAN cannot have more than 239 FCF switches.
An FC SAN needs a large number of edge switches that connect directly to nodes. N_Port Virtualization
(NPV) switches are developed to expand the number of switches in an FC SAN.
10, different from a pure FC network, the ENode and FCF