Enhanced small form-factor pluggable transceiver

The small form-factor pluggable (SFP) is a compact, hot-pluggable optical module transceiver used for both telecommunication and data communications applications. The form factor and electrical interface are specified by a multi-source agreement (MSA) under the auspices of the Small Form Factor Committee. It is a popular industry format jointly developed and supported by many network component vendors.

An SFP interface on networking hardware provides the device with a modular interface that the user can easily adapt to various fiber optic and copper networking standards. SFP transceivers exist supporting SONET, gigabit Ethernet, Fibre Channel, and other communications standards. Due to its smaller size, the SFP has replaced the gigabit interface converter (GBIC) in most applications; the SFP is sometimes referred to as a Mini-GBIC. In fact, no device with this name has ever been officially defined in the MSAs.

SFP transceivers are available with a variety of transmitter and receiver types, allowing users to select the appropriate transceiver for each link to provide the required optical reach over the available optical fiber type (e.g. multi-mode fiber or single-mode fiber). Transceivers are most often designated by the standard transmission speed on the medium (e.g. 1.25 Gbit/s for Gigabit Ethernet or 10.3125 Gbit/s for 10 Gigabit Ethernet), but sometimes they are labeled with their nominal Ethernet speed or a higher speed the manufacturer specifies. SFP modules are commonly available in several different categories:

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