A small Form-Factor Pluggable Transceiver – SFP transceiver is a compact, hot-swappable, input/output transceiver used in data communication and telecommunications networks. SFP interfaces between communication devices like switches, routers and fiber optic cables, and performs conversions between optical and electrical signals. SFP transceivers support communications standards including synchronous optical networking (SONET)/synchronous digital hierarchy (SDH), gigabit ethernet and fiber channel. They also allow the transport of fast Ethernet and gigabit Ethernet LAN packets over time-division-multiplexing-based WANs, as well as the transmission of E1/T1 streams over packet-switched networks.
Cisco Fast Ethernet SFP Modules
SFP is also called a mini gigabit interface converter (GBIC) because its function is similar to the GBIC transceiver but with much smaller dimensions.
Compact SFP Deployment with Cisco Catalyst 4500
Bidirectional Transmission of a Single Strand of SMF
Ethernet switch with empty SFP slots (lower left)
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| Pin | Name | Function |
|---|---|---|
| 1 | VeeT | Transmitter ground |
| 2 | TxFault | Transmitter fault indication |
| 3 | TxDisable | Optical output disabled when high |
| 4 | MOD-DEF(2) | Data for serial ID interface |
| 5 | MOD-DEF(1) | Clock for serial ID interface |
| 6 | MOD-DEF(0) | Grounded by the module to indicate module presence |
| 7 | RateSelect | Low selects reduced bandwidth |
| 8 | LOS | When high, indicates received optical power below worst-case receiver sensitivity |
| 9 | VeeR | Receiver ground |
| 10 | VeeR | Receiver ground |
| 11 | VeeR | Receiver ground |
| 12 | RD- | Inverted received data |
| 13 | RD+ | Received data |
| 14 | VeeR | Receiver ground |
| 15 | VccR | Receiver power (3.3 V) |
| 16 | VccT | Transmitter power (3.3 V) |
| 17 | VeeT | Transmitter ground |
| 18 | TD+ | Transmit data |
| 19 | TD- | Inverted transmit data |
| 20 | VeeT | Transmitter ground |
Source : https://www.techopedia.com/definition/24949/small-form-factor-pluggable-transceiver-sfp
Source : http://www.cisco.com/c/en/us/support/docs/interfaces-modules/cwdm-gbic-sfp/72370-sfp-trcvr-mods.html
Source : https://en.wikipedia.org/wiki/Small_form-factor_pluggable_transceiver