Fibre channel ports

The Key elements of fibre channel network are the end systems; they are called as nodes. A collection of switching elements is referred to as a fabric. The elements are interconnected by a point-to-point links between ports on the single nodes and switches.

Types of ports:

  • N_port, NL_port (Node port, Node Loop port)
  • F_port, FL_port (Fabric port, Fabric Loop port)
  • E_port, EX_port (Expansion port)
  • TE_port (Trunking Expansion port)
  • G_port (Generic port)
  • L_port (Loop port)
  • U_port (Universal port)

N_port, NL_port are comes below the type node port, F_port, FL_port, E_port, EX_port, TE_port are comes below the type switch/router ports, G_port, L_port, U_port are the port which comes below the type general ports.

Switching Network:

A fibre channel network is totally different from the IEEE 802 LANs. Fibre channel is more like a traditional circuit-switching or packet switching network. The fibre channels need to be concerned with a medium access control. Because it is based on a switching network, the fibre channel scales easily in terms of N_port, data rate and distance covered. This approaches provides a great flexibility. Fibre channel can eagerly accommodate new transmission media and data rates adding new switches and F_port to an existing fabric. Thus an existing asset is not lost with an upgrade to new technologies and equipment. The layered protocol architecture provides accommodation to an existing I/O interface and networking protocols.

Fibre channel protocol architecture:

The fibre channel standard is organized into five levels, each levels defines a set of related functions. The five level protocols are

  • FC-0 Physical Media is used optical fibre for long distance and coaxial cable for high speeds and twisted pair for lower speed over a short distance.
  • FC-1 Transmission Protocol is the signal encoding scheme.
  • FC-2 Framing Protocol deals with defining topologies, frame format, flow and error control, this grouping of frames are called as sequences and exchanges.
  • FC-3 Common Services includes multicasting.
  • FC-4 mapping of various channel and network protocol to fibre channel, including IEEE 802, ATM, IP and SCSI.