C Form-factor Pluggable

From Wikipedia, the free encyclopedia
Jump to: navigation, search

The C form-factor pluggable (CFP) is a multi-source agreement to produce a common form-factor for the transmission of high-speed digital signals. The c stands for the Latin letter C used to express the number 100 (centum), since the standard was primarily developed for 100 Gigabit Ethernet systems.

CFP standardization[edit]

The CFP transceiver is specified by a multi-source agreement (MSA) between competing manufacturers. The CFP was designed after the small form-factor pluggable transceiver (SFP) interface, but is significantly larger to support 100 Gbit/s. While the electrical connection of a CFP uses 10 x 10 Gbit/s lanes in each direction (RX, TX)[1] the optical connection can support both 10 x 10 Gbit/s and 4 x 25 Gbit/s variants of 100 Gbit/s interconnects (typically referred to as 100GBASE-SR10 in 100 meter MMF, 100GBASE-LR10 and 100GBASE-LR4 in 10 km SMF reach, and 100GBASE-ER10 and 100GBASE-ER4 in 40 km SMF reach respectively.)[2]

In March 2009, Santur Corporation demonstrated a 100 Gigabit pluggable CFP transceiver prototype.[3]

Supported signals[edit]

CFP transceivers can support a single 100 Gbit/s signal like 100GbE or OTU4 or one or more 40 Gbit/s signals like 40GbE, OTU3, or STM-256/OC-768.

Variants[edit]

The original CFP specification was proposed at a time when 10Gbps signals were far more achievable than 25Gbps signals. As such to achieve 100Gbps line rate, the most affordable solution was based on 10 lanes of 10Gbps. However as expected, improvements in technology has allowed higher performance and higher density. Hence the development of the CFP2 and CFP4 specifications. While electrical similar, they specify a form-factor of 1/2 and 1/4 respectively in size of the original specification. Note that CFP, CFP2 and CFP4 modules are not interchangeable (but would be inter-operable at the optical interface with appropriate connectors).

CFP[1][edit]

  • 148 pin electrical connection
  • integrated digital signal processor within package
  • less than 24W power usage
  • 10x10G or 4x25G lanes

CFP2[4][edit]

  • 104 pin electrical connection
  • no digital signal processor in package, relies on host card
  • less than 12w power usage
  • 10x10G or 4x25G or 8x25G lanes

CFP4[5][edit]

  • 56 pin electrical connection
  • no digital signal processor in package, relies on host card
  • less than 6w power usage
  • 10x10G or 4x25G lanes

MSA 5"x7" (Gen 1)[6][7][edit]

  • 168 pin electrical connection (designed to be built into a line card)
  • digital signal processor within package
  • less than 80w power usage

MSA 4"x5" (Gen 2)[edit]

  • 168 pin electrical connection (designed to be built into a line card)
  • digital signal processor within package
  • less than 40w power usage

See also[edit]

References[edit]

External links[edit]