Which of the following is a SAN protocol?

FCoE (Fibre Channel over Ethernet) is a storage networking protocol that encapsulates Fibre Channel frames over full-duplex Ethernet networks. It allows Fibre Channel traffic to run on standard Ethernet infrastructure, making it a key protocol for converging SAN and LAN traffic.

DCB (Data Center Bridging) is a set of IEEE standards that extend Ethernet to support lossless transmission, which is crucial for protocols like FCoE, but DCB itself is not a SAN protocol.

DTE (Data Terminal Equipment) refers to end-user devices in telecommunications, like computers or routers, and is not a SAN protocol.

IDE (Integrated Drive Electronics) is an interface standard for connecting storage devices like hard drives directly to a computer's motherboard, not a network protocol used in a SAN.