Small Form-factor Pluggable
Small Form-factor Pluggable (SFP) is a compact, hot-pluggable network interface module format used for both telecommunication and data communications applications. An SFP interface on networking hardware is a modular slot for a media-specific transceiver, such as for a fiber-optic cable or a copper cable. The advantage of using SFPs compared to fixed interfaces (e.g. modular connectors in Ethernet switches) is that individual ports can be equipped with different types of transceivers as required, with the majority of devices including optical line terminals, network cards, switches and routers. The form factor and electrical interface are specified by a multi-source agreement (MSA) under the auspices of the Small Form Factor Committee. The SFP replaced the larger gigabit interface converter (GBIC) in most applications, and has been referred to as a Mini-GBIC by some vendors. SFP transceivers exist supporting synchronous optical networking (SONET), Gigabit Ethernet, Fibre Channel, PON, and other communications standards. At introduction, typical speeds were 1 Gbit/s for Ethernet SFPs and up to 4 Gbit/s for Fibre Channel SFP modules. In 2006, SFP+ specification brought speeds up to 10 Gbit/s and the later SFP28 iteration, introduced in 2014, is designed for speeds of 25 Gbit/s. A slightly larger sibling is the four-lane Quad Small Form-factor Pluggable (QSFP). The additional lanes allow for speeds 4 times their corresponding SFP. In 2014, the QSFP28 variant was published allowing speeds up to 100 Gbit/s. In 2019, the closely related QSFP56 was standardized doubling the top speeds to 200 Gbit/s with products already selling from major vendors. There are inexpensive adapters allowing SFP transceivers to be placed in a QSFP port. Both a SFP-DD, which allows for 100 Gbit/s over two lanes, as well as a QSFP-DD specifications, which allows for 400 Gbit/s over eight lanes, have been published. These use a form factor which is directly backward compatible to their respective predecessors. An even larger sibling, the Octal Small Format Pluggable (OSFP), had products released in 2022 capable of 800 Gbit/s links between network equipment. It is a slightly larger version than the QSFP form factor allowing for larger power outputs. The OSFP standard was initially announced in 2016 with the 4.0 version released in 2021 allowing for 800 Gbit/s via 8×100 Gbit/s electrical data lanes. Its proponents say a low-cost adapter will allow for backwards compatibility with QSFP modules.
Small Form-factor Pluggable (SFP) is a compact, hot-pluggable network interface module format used for both telecommunication and data communications applications. An SFP interface on networking hardware is a modular slot for a media-specific transceiver, such as for a fiber-optic cable or a copper cable.[1] The advantage of using SFPs compared to fixed interfaces (e.g. modular connectors in Ethernet switches) is that individual ports can be equipped with different types of transceivers as required, with the majority of devices including optical line terminals, network cards, switches and routers.
The form factor and electrical interface are specified by a multi-source agreement (MSA) under the auspices of the Small Form Factor Committee.[2] The SFP replaced the larger gigabit interface converter (GBIC) in most applications, and has been referred to as a Mini-GBIC by some vendors.[3]
SFP transceivers exist supporting synchronous optical networking (SONET), Gigabit Ethernet, Fibre Channel, PON, and other communications standards. At introduction, typical speeds were 1 Gbit/s for Ethernet SFPs and up to 4 Gbit/s for Fibre Channel SFP modules.[4] In 2006, SFP+ specification brought speeds up to 10 Gbit/s and the later SFP28 iteration, introduced in 2014,[5] is designed for speeds of 25 Gbit/s.[6]
A slightly larger sibling is the four-lane Quad Small Form-factor Pluggable (QSFP). The additional lanes allow for speeds 4 times their corresponding SFP. In 2014, the QSFP28 variant was published allowing speeds up to 100 Gbit/s.[7] In 2019, the closely related QSFP56 was standardized[8] doubling the top speeds to 200 Gbit/s with products already selling from major vendors.[9] There are inexpensive adapters allowing SFP transceivers to be placed in a QSFP port.
Both a SFP-DD,[10] which allows for 100 Gbit/s over two lanes, as well as a QSFP-DD[11] specifications, which allows for 400 Gbit/s over eight lanes, have been published.[12] These use a form factor which is directly backward compatible to their respective predecessors.[13]
An even larger sibling, the Octal Small Format Pluggable (OSFP), had products released in 2022[14] capable of 800 Gbit/s links between network equipment. It is a slightly larger version than the QSFP form factor allowing for larger power outputs. The OSFP standard was initially announced in 2016[15] with the 4.0 version released in 2021 allowing for 800 Gbit/s via 8×100 Gbit/s electrical data lanes.[16] Its proponents say a low-cost adapter will allow for backwards compatibility with QSFP modules.[17]
SFP types
[edit]SFP transceivers are available with a variety of transmitter and receiver specifications, allowing users to select the appropriate transceiver for each link to provide the required optical or electrical reach over the available media type (e.g. twisted pair or twinaxial copper cables, multi-mode or single-mode fiber cables). Transceivers are also designated by their transmission speed. SFP modules are commonly available in several different categories.
| Name | Nominal speed |
Lanes | Standard | Introduced | Backward-compatible | PHY interface | Connector |
|---|---|---|---|---|---|---|---|
| SFP | 100 Mbit/s | 1 | SFF INF-8074i | 2001-05-01 | None | MII | LC, RJ45 |
| SFP | 1 Gbit/s | 1 | SFF INF-8074i | 2001-05-01 | 100 Mbit/s SFP* | SGMII | LC, RJ45 |
| cSFP | 1 Gbit/s | 2 | LC | ||||
| SFP+ | 10 Gbit/s | 1 | SFF SFF-8431 4.1 | 2009-07-06 | SFP | XGMII | LC, RJ45 |
| SFP28 | 25 Gbit/s | 1 | SFF SFF-8402 | 2014-09-13 | SFP, SFP+ | LC | |
| SFP56 | 50 Gbit/s | 1 | SFP, SFP+, SFP28 | LC | |||
| SFP-DD | 100 Gbit/s | 2 | SFP-DD MSA[18] | 2018-01-26 | SFP, SFP+, SFP28, SFP56 | LC | |
| SFP112 | 100 Gbit/s | 1 | 2018-01-26 | SFP, SFP+, SFP28, SFP56 | LC | ||
| SFP-DD112 | 200 Gbit/s | 2 | 2018-01-26 | SFP, SFP+, SFP28, SFP56, SFP-DD, SFP112 | LC | ||
| QSFP types | |||||||
| QSFP | 4 Gbit/s | 4 | SFF INF-8438 | 2006-11-01 | None | GMII | |
| QSFP+ | 40 Gbit/s | 4 | SFF SFF-8436 | 2012-04-01 | None | XGMII | LC, MTP/MPO |
| QSFP28 | 50 Gbit/s | 2 | SFF SFF-8665 | 2014-09-13 | QSFP+ | LC | |
| QSFP28 | 100 Gbit/s | 4 | SFF SFF-8665 | 2014-09-13 | QSFP+ | LC, MTP/MPO-12 | |
| QSFP56 | 200 Gbit/s | 4 | SFF SFF-8665 | 2015-06-29 | QSFP+, QSFP28 | LC, MTP/MPO-12 | |
| QSFP112 | 400 Gbit/s | 4 | SFF SFF-8665 | 2015-06-29 | QSFP+, QSFP28, QSFP56 | LC, MTP/MPO-12 | |
| QSFP-DD | 400 Gbit/s | 8 | SFF INF-8628 | 2016-06-27 | QSFP+, QSFP28,[19] QSFP56 | LC, MTP/MPO-16 | |
Note that the QSFP/QSFP+/QSFP28/QSFP56 are designed to be electrically backward compatible with SFP/SFP+/SFP28 or SFP56 respectively. Using a simple adapter or a special direct attached cable it is possible to connect those interfaces together using just one lane instead of four provided by the QSFP/QSFP+/QSFP28/QSFP56 form factor. The same applies to the QSFP-DD form factor with 8 lanes which can work downgraded to 4/2/1 lanes.
100 Mbit/s SFP
[edit]- Multi-mode fiber, LC connector, with black or Beige color coding
- SX – 850 nm, for a maximum of 550 m
- Multi-mode fiber, LC connector, with blue color coding
- Single-mode fiber, LC connector, with blue color coding
- Single-mode fiber, LC connector, with green color coding
- ZX – 1550 nm, for distances up to 80 km, (depending on fiber path loss)
- EZX – 1550 nm, for distances up to 160 km (depending on fiber path loss)
- Single-mode fiber, LC connector, Bi-Directional, with blue and yellow color coding
- BX (officially BX10) – 1550 nm/1310 nm, Single Fiber Bi-Directional 100 Mbit SFP Transceivers, paired as BX-U (blue) and BX-D (yellow) for uplink and downlink respectively, also for distances up to 10 km. Variations of bidirectional SFPs are also manufactured which higher transmit power versions with link length capabilities up to 40 km.
- Copper twisted-pair cabling, 8P8C (RJ-45) connector
- 100BASE-TX – for distances up to 100m.
1 Gbit/s SFP
[edit]- 1 to 1.25 Gbit/s multi-mode fiber, LC connector, with black or beige extraction lever[2]
- SX – 850 nm, for a maximum of 550 m at 1.25 Gbit/s (gigabit Ethernet). Other multi-mode SFP applications support even higher rates at shorter distances.[20]
- 1 to 1.25 Gbit/s multi-mode fiber, LC connector, extraction lever colors not standardized
- SX+/MX/LSX/LX (name dependent on manufacturer) – 1310 nm, for a distance up to 2 km.[21] Not compatible with SX or 100BASE-FX. Based on LX but engineered to work with a multi-mode fiber using a standard multi-mode patch cable rather than a mode-conditioning cable commonly used to adapt LX to multi-mode.
- 1 to 2.5 Gbit/s single-mode fiber, LC connector, with blue extraction lever[2]
- LX – 1310 nm, for distances up to 10 km (originally, LX just covered 5 km and LX10 for 10 km followed later)
- EX – 1310 nm, for distances up to 40 km
- ZX – 1550 nm, for distances up to 80 km (depending on fiber path loss), with green extraction lever (see GLC-ZX-SM1)
- EZX – 1550 nm, for distances up to 160 km (depending on fiber path loss)
- BX (officially BX10) – 1490 nm/1310 nm, Single Fiber Bi-Directional Gigabit SFP Transceivers, paired as BX-U and BX-D for uplink and downlink respectively, also for distances up to 10 km.[22][23] Variations of bidirectional SFPs are also manufactured which use 1550 nm in one direction, and higher transmit power versions with link length capabilities up to 80 km.
- 1550 nm 40 km (XD), 80 km (ZX), 120 km (EX or EZX)
- SFSW – single-fiber single-wavelength transceivers, for bi-directional traffic on a single fiber. Coupled with CWDM, these double the traffic density of fiber links.[24][25]
- Coarse wavelength-division multiplexing (CWDM) and dense wavelength-division multiplexing (DWDM) transceivers at various wavelengths achieve various maximum distances. CWDM and DWDM transceivers usually support link distances of 40, 80 and 120 km.
- 1 Gbit/s for copper twisted-pair cabling, 8P8C (RJ-45) connector
- 1000BASE-T – these modules incorporate significant interface circuitry for Physical Coding Sublayer recoding[26] and can be used only for gigabit Ethernet because of the specific line code. They are not compatible with (or rather: do not have equivalents for) Fibre Channel or SONET. Unlike most non-SFP, copper 1000BASE-T ports integrated into most routers and switches, 1000BASE-T SFPs usually cannot operate at 100BASE-TX speeds.
- 100 Mbit/s copper and optical – some vendors have shipped 100 Mbit/s limited SFPs for fiber-to-the-home applications and drop-in replacement of legacy 100BASE-FX circuits. These are relatively uncommon and can be easily confused with 100 Mbit/s SFPs.[27]
- Although it is not mentioned in any official specification document the maximum data rate of the original SFP standard is 5 Gbit/s.[28] This was eventually used by both 4GFC Fibre Channel and the DDR Infiniband especially in its four-lane QSFP form.
- In recent years,[when?] SFP transceivers have been created that will allow 2.5 Gbit/s and 5 Gbit/s Ethernet speeds with SFPs with 2.5GBASE-T[29] and 5GBASE-T.[30]
10 Gbit/s SFP+
[edit]
The SFP+ (enhanced small form-factor pluggable) is an enhanced version of the SFP that supports data rates up to 16 Gbit/s. The SFP+ specification was first published on May 9, 2006, and version 4.1 was published on July 6, 2009.[31] SFP+ supports 8 Gbit/s Fibre Channel, 10 Gigabit Ethernet and Optical Transport Network standard OTU2. It is a popular industry format supported by many network component vendors. Although the SFP+ standard does not include mention of 16 Gbit/s Fibre Channel, it can be used at this speed.[32] Besides the data rate, the major difference between 8 and 16 Gbit/s Fibre Channel is the encoding method. The 64b/66b encoding used for 16 Gbit/s is a more efficient encoding mechanism than 8b/10b used for 8 Gbit/s, and allows for the data rate to double without doubling the line rate. 16GFC doesn't really use 16 Gbit/s signaling anywhere. It uses a 14.025 Gbit/s line rate to achieve twice the throughput of 8GFC.[33]
SFP+ also introduces direct attach for connecting two SFP+ ports without dedicated transceivers. Direct attach cables (DAC) exist in passive (up to 7 m), active (up to 15 m), and active optical (AOC, up to 100 m) variants.
10 Gbit/s SFP+ modules are exactly the same dimensions as regular SFPs, allowing the equipment manufacturer to re-use existing physical designs for 24 and 48-port switches and modular line cards. In comparison to earlier XENPAK or XFP modules, SFP+ modules leave more circuitry to be implemented on the host board instead of inside the module.[34] Through the use of an active electronic adapter, SFP+ modules may be used in older equipment with XENPAK ports [35] and X2 ports.[36][37]
SFP+ modules can be described as limiting or linear types; this describes the functionality of the inbuilt electronics. Limiting SFP+ modules include a signal amplifier to re-shape the (degraded) received signal whereas linear ones do not. Linear modules are mainly used with the low bandwidth standards such as 10GBASE-LRM; otherwise, limiting modules are preferred.[38]
25 Gbit/s SFP28
[edit]SFP28 is a 25 Gbit/s interface which evolved from the 100 Gigabit Ethernet interface which is typically implemented with 4 by 25 Gbit/s data lanes. Identical in mechanical dimensions to SFP and SFP+, SFP28 implements one 28 Gbit/s lane[39] accommodating 25 Gbit/s of data with encoding overhead.[40]
SFP28 modules exist supporting single-[41] or multi-mode[42] fiber connections, active optical cable[43] and direct attach copper.[44][45]
cSFP
[edit]The compact small form-factor pluggable (cSFP) is a version of SFP with the same mechanical form factor allowing two independent bidirectional channels per port. It is used primarily to increase port density and decrease fiber usage per port.[46][47]
SFP-DD
[edit]The small form-factor pluggable double density (SFP-DD) multi-source agreement is a standard published in 2019 for doubling port density. According to the SFD-DD MSA website: "Network equipment based on the SFP-DD will support legacy SFP modules and cables, and new double density products."[48] SFP-DD uses two lanes to transmit.
Currently, the following speeds are defined:
- SFP112: 100 Gbit/s using PAM4 on a single pair (not double density)[18]
- SFP-DD: 100 Gbit/s using PAM4 and 50 Gbit/s using NRZ[18]
- SFP-DD112: 200 Gbit/s using PAM4[18]
- QSFP112: 400 Gbit/s (4 × 112 Gbit/s)[49]
- QSFP-DD: 400 Gbit/s/200 Gbit/s (8 × 50 Gbit/s and 8 × 25 Gbit/s)[50]
- QSFP-DD800 (formerly QSFP-DD112): 800 Gbit/s (8 × 112 Gbit/s)[49]
- QSFP-DD1600 (Draft) 1.6 Tbit/s[51]
QSFP
[edit]
Quad Small Form-factor Pluggable (QSFP) 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 multi-mode or single-mode fiber.
- 4 Gbit/s
- The original QSFP document specified four channels carrying Gigabit Ethernet, 4GFC (FiberChannel), or DDR InfiniBand.[52]
- 40 Gbit/s (QSFP+)
- QSFP+ is an evolution of QSFP to support four 10 Gbit/s channels carrying 10 Gigabit Ethernet, 10GFC FiberChannel, or QDR InfiniBand.[53] The 4 channels can also be combined into a single 40 Gigabit Ethernet link.
- 50 Gbit/s (QSFP14)
- The QSFP14 standard is designed to carry FDR InfiniBand, SAS-3[54] or 16G Fibre Channel.
- 100 Gbit/s (QSFP28)
- The QSFP28 standard[7] is designed to carry 100 Gigabit Ethernet, EDR InfiniBand, or 32G Fibre Channel. Sometimes this transceiver type is also referred to as QSFP100 or 100G QSFP[55] for sake of simplicity.
- 200 Gbit/s (QSFP56)
- QSFP56 is designed to carry 200 Gigabit Ethernet, HDR InfiniBand, or 64G Fibre Channel. The biggest enhancement is that QSFP56 uses four-level pulse-amplitude modulation (PAM-4) instead of non-return-to-zero (NRZ). It uses the same physical specifications as QSFP28 (SFF-8665), with electrical specifications from SFF-8024[56] and revision 2.10a of SFF-8636.[8] Sometimes this transceiver type is referred to as 200G QSFP[57] for sake of simplicity.
Switch and router manufacturers implementing QSFP+ ports in their products frequently allow for the use of a single QSFP+ port as four independent 10 Gigabit Ethernet connections, greatly increasing port density. For example, a typical 24-port QSFP+ 1U switch would be able to service 96x10GbE connections.[58][59][60] There also exist fanout cables to adapt a single QSFP28 port to four independent 25 Gigabit Ethernet SFP28 ports (QSFP28-to-4×SFP28)[61] as well as cables to adapt a single QSFP56 port to four independent 50 Gigabit Ethernet SFP56 ports (QSFP56-to-4×SFP56).[62]
Applications
[edit]
SFP sockets are found in Ethernet switches, routers, firewalls and network interface cards. They are used in Fibre Channel host adapters and storage equipment. Because of their low cost, low profile, and ability to provide a connection to different types of optical fiber, SFP provides such equipment with enhanced flexibility.
SFP sockets and transceivers are also used for long-distance serial digital interface (SDI) transmission.[63]
Standardization
[edit]The SFP transceiver is not standardized by any official standards body, but rather is specified by a multi-source agreement (MSA) among competing manufacturers. The SFP was designed after the GBIC interface, and allows greater port density (number of transceivers per given area) than the GBIC, which is why SFP is also known as mini-GBIC.
However, as a practical matter, some networking equipment manufacturers engage in vendor lock-in practices whereby they deliberately break compatibility with generic SFPs by adding a check in the device's firmware that will enable only the vendor's own modules.[64] Third-party SFP manufacturers have introduced SFPs with EEPROMs which may be programmed to match any vendor ID.[65]
Color coding of SFP
[edit]Color coding of SFP
[edit]| Color | Standard | Media | Wavelength | Notes |
|---|---|---|---|---|
Black |
INF-8074 | Multimode | 850 nm | |
| Beige | INF-8074 | Multimode | 850 nm | |
Black |
INF-8074 | Multimode | 1300 nm | |
Blue |
INF-8074 | Singlemode | 1310 nm | |
| Red | proprietary (non SFF) |
Singlemode | 1310 nm | Used on 25GBASE-ER[66] |
| Green | proprietary (non SFF) |
Singlemode | 1550 nm | Used on 100BASE-ZE |
| Red | proprietary (non SFF) |
Singlemode | 1550 nm | Used on 10GBASE-ER |
| White | proprietary (non SFF) |
Singlemode | 1550 nm | Used on 10GBASE-ZR |
Color coding of CWDM SFP
[edit]See also: coarse wavelength-division multiplexing
| Color[67] | Standard | Wavelength | Notes |
|---|---|---|---|
| Grey | 1270 nm | ||
| Grey | 1290 nm | ||
| Grey | 1310 nm | ||
| Violet | 1330 nm | ||
| Blue | 1350 nm | ||
| Green | 1370 nm | ||
| Yellow | 1390 nm | ||
| Orange | 1410 nm | ||
| Red | 1430 nm | ||
| Brown | 1450 nm | ||
| Grey | 1470 nm | ||
| Violet | 1490 nm | ||
| Blue | 1510 nm | ||
| Green | 1530 nm | ||
| Yellow | 1550 nm | ||
| Orange | 1570 nm | ||
| Red | 1590 nm | ||
| Brown | 1610 nm |
Color coding of BiDi SFP
[edit]| Name | Standard | Side A Color TX | Side A wavelength TX | Side B Color TX | Side B wavelength TX | Notes |
|---|---|---|---|---|---|---|
| 1000BASE-BX | Blue | 1310 nm | Purple | 1490 nm | ||
| 1000BASE-BX | Blue | 1310 nm | Yellow | 1550 nm | ||
| 10GBASE-BX 25GBASE-BX |
Blue | 1270 nm | Red | 1330 nm | ||
| 10GBASE-BX | White | 1490 nm | White | 1550 nm |
Color coding of QSFP
[edit]| Color | Standard | Wavelength | Multiplexing | Notes |
|---|---|---|---|---|
| Beige | INF-8438 | 850 nm | No | |
| Blue | INF-8438 | 1310 nm | No | |
| White | INF-8438 | 1550 nm | No |
Signals
[edit]
When looking into the optical connectors, the one on the left is the transmitter and the one on the right is the receiver.[68]
The SFP transceiver contains a printed circuit board with an edge connector with 20 pads that mate on the rear with the SFP electrical connector in the host system. The QSFP has 38 pads including 4 high-speed transmit data pairs and 4 high-speed receive data pairs.[52][53]
| Pad | Name | Function |
|---|---|---|
| 1 | VeeT | Transmitter ground |
| 2 | Tx_Fault | Transmitter fault indication |
| 3 | Tx_Disable | Optical output disabled when high |
| 4 | SDA | 2-wire serial interface data line (using the CMOS EEPROM protocol defined for the ATMEL AT24C01A/02/04 family[69]) |
| 5 | SCL | 2-wire serial interface clock |
| 6 | Mod_ABS | Module absent, connection to VeeT or VeeR in the module indicates module presence to host |
| 7 | RS0 | Rate select 0 |
| 8 | Rx_LOS | Receiver loss of signal indication |
| 9 | RS1 | Rate select 1 |
| 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, max. 300 mA) |
| 16 | VccT | Transmitter power (3.3 V, max. 300 mA) |
| 17 | VeeT | Transmitter ground |
| 18 | TD+ | Transmit data |
| 19 | TD- | Inverted transmit data |
| 20 | VeeT | Transmitter ground |
| Pad | Name | Function |
|---|---|---|
| 1 | GND | Ground |
| 2 | Tx2n | Transmitter inverted data input |
| 3 | Tx2p | Transmitter non-inverted data input |
| 4 | GND | Ground |
| 5 | Tx4n | Transmitter inverted data input |
| 6 | Tx4p | Transmitter non-inverted data input |
| 7 | GND | Ground |
| 8 | ModSelL | Module select |
| 9 | ResetL | Module reset |
| 10 | Vcc-Rx | +3.3 V receiver power supply |
| 11 | SCL | Two-wire serial interface clock |
| 12 | SDA | Two-wire serial interface data |
| 13 | GND | Ground |
| 14 | Rx3p | Receiver non-inverted data output |
| 15 | Rx3n | Receiver inverted data output |
| 16 | GND | Ground |
| 17 | Rx1p | Receiver non-inverted data output |
| 18 | Rx1n | Receiver inverted data output |
| 19 | GND | Ground |
| 20 | GND | Ground |
| 21 | Rx2n | Receiver inverted data output |
| 22 | Rx2p | Receiver non-inverted data output |
| 23 | GND | Ground |
| 24 | Rx4n | Receiver inverted data output |
| 25 | Rx4p | Receiver non-inverted data output |
| 26 | GND | Ground |
| 27 | ModPrsL | Module present |
| 28 | IntL | Interrupt |
| 29 | Vcc-Tx | +3.3 V transmitter power supply |
| 30 | Vcc1 | +3.3 V power supply |
| 31 | LPMode | Low power mode |
| 32 | GND | Ground |
| 33 | Tx3p | Transmitter non-inverted data input |
| 34 | Tx3n | Transmitter inverted data input |
| 35 | GND | Ground |
| 36 | Tx1p | Transmitter non-inverted data input |
| 37 | Tx1n | Transmitter inverted data input |
| 38 | GND | Ground |
Mechanical dimensions
[edit]
The physical dimensions of the SFP transceiver (and its subsequent faster variants) are narrower than the later QSFP counterparts, which allows for SFP transceivers to be placed in QSFP ports via an inexpensive adapter. Both are smaller than the XFP transceiver.
SFP modules that use SC fiber connectors don't always indicate whether they use SC/APC (angled) or SC/UPC (ultra polished) connections. SC/UPC is the most common.
| SFP[2] | QSFP[52] | XFP[70] | ||||
|---|---|---|---|---|---|---|
| mm | in | mm | in | mm | in | |
| Height | 8.5 | 0.33 | 8.5 | 0.33 | 8.5 | 0.33 |
| Width | 13.4 | 0.53 | 18.35 | 0.722 | 18.35 | 0.722 |
| Depth | 56.5 | 2.22 | 72.4 | 2.85 | 78.0 | 3.07 |
EEPROM information and Management Interface
[edit]The SFP MSA defines a 256-byte memory map into an EEPROM describing the transceiver's capabilities, standard interfaces, manufacturer, and other information, which is accessible over a serial I²C interface at the 8-bit address 0b1010000X (0xA0).[71]
Later standards also specify (volatile) memory locations which offer the ability to observe and change the behavior of the transceiver.
| Form factor | Management interface standard |
|---|---|
| SFP+ | SFF-8472 |
| QSFP+ | SFF-8636 |
Digital diagnostics monitoring
[edit]Modern optical SFP transceivers support standard digital diagnostics monitoring (DDM) functions.[72] This feature is also known as digital optical monitoring (DOM). This capability allows monitoring of the SFP operating parameters in real time. Parameters include optical output power, optical input power, temperature, laser bias current, and transceiver supply voltage. In network equipment, this information is typically made available via Simple Network Management Protocol (SNMP). A DDM interface allows end users to display diagnostics data and alarms for optical fiber transceivers and can be used to diagnose why a transceiver is not working.
See also
[edit]References
[edit]- ^ "SFP Definition from PC Magazine Encyclopedia". www.pcmag.com. Retrieved May 10, 2018.
- ^ a b c d e SFF Committee (May 12, 2001), INF-8074i Specification for SFP (Small Formfactor Pluggable) Transceiver, retrieved April 30, 2020
- ^ "Cisco MGBSX1 Gigabit SX Mini-GBIC SFP Transceiver". Retrieved March 25, 2018.
- ^ "4G Fibre Channel SFP". Flexoptix GmbH. Retrieved October 5, 2019.[unreliable source?]
- ^ "DRAFT SFF-8402 CB". SNIA Members. Storage Networking Industry Association (SNIA). December 2, 2022. Retrieved September 24, 2024.
- ^ "SFF-8402: SFP+ 1X 28 Gb/s Pluggable Transceiver Solution (SFP28)". 1.9. SNIA SFF Committee. September 13, 2014. Retrieved March 26, 2019.
- ^ a b "SFF-8665: QSFP+ 28 Gb/s 4X Pluggable Transceiver Solution (QSFP28)". 1.9. SNIA SFF Committee. June 29, 2015. Retrieved March 26, 2019.
- ^ a b "Management Interface for 4-lane Modules and Cables". SFF-8636 (Rev 2.10a ed.). SNIA SFF Committee. September 24, 2019. Retrieved October 11, 2019.
- ^ "Mellanox Quantum 8700 40 port QSFP56 Product Brief" (PDF).[unreliable source?][dead link]
- ^ "SFP-DD MSA".
- ^ "QSFP-DD MSA".
- ^ "Lightwave Online news article re: 400Gb". November 18, 2016.
- ^ "Backward Compatibility: QSFP-DD/QSFP28/QSFP+/SFP+". Derek. Retrieved July 21, 2022.[unreliable source?]
- ^ "Introduction - NVIDIA QM97X0 NDR SWITCH SYSTEMS USER MANUAL - NVIDIA Networking Docs". docs.nvidia.com. Retrieved January 18, 2022.
- ^ "OSFP MSA".
- ^ "OSFP MSA Announces Release of OSFP 4.0 Specification for 800G Modules". www.osfpmsa.org (Press release). Retrieved January 18, 2022.
With the 800G spec completed, group is developing specification for 1600G modules
- ^ "OSFP to QSFP Adapter" (PDF). Retrieved November 2, 2021.
- ^ a b c d SFP-DD MSA (March 11, 2022). "SFP-DD/SFP-DD112/SFP112 Hardware Specification for SFP112 AND SFP DOUBLE DENSITY PLUGGABLE TRANSCEIVER Revision 5.1" (PDF).
- ^ "Cisco 400G QSFP-DD Cable and Transceiver Modules Data Sheet". Cisco. Retrieved March 27, 2020.
- ^ Agilestar/Finisar FTLF8524P2BNV specification (PDF)
- ^ "PROLINE 1000BASE-SX EXT MMF SFP F/CISCO 1310NM 2KM - SFP-MX-CDW - Ethernet Transceivers". CDW.com. Retrieved January 2, 2017.[unreliable source?]
- ^ Single Fiber Bidirectional SFP Transceiver (PDF), MRV, archived from the original (PDF) on April 19, 2016[unreliable source?]
- ^ Gigabit Bidirectional SFPs, Yamasaki Optical Technology
- ^ "Single-fiber single-wavelength gigabit transceivers". Lightwave. September 5, 2002. Retrieved September 5, 2002.[unreliable source?]
- ^ "The principle of Single Wavelength BiDi Transceiver". Gigalight. Archived from the original on April 3, 2014.[unreliable source?]
- ^ VSC8211 media converter/physical layer specification[unreliable source?][dead link]
- ^ "Fiberstore: 100 M SFPs".[unreliable source?]
- ^ "FAQs for SFP+". The Siemon Company. August 20, 2010. Retrieved February 22, 2016.[unreliable source?][dead link]
- ^ "2.5GBASE-T Copper SFP". Flexoptix GmbH. Retrieved October 4, 2019.
- ^ "5GBASE-T Copper SFP". Flexoptix GmbH. Retrieved October 4, 2019.[unreliable source?]
- ^ "SFF-8431 Specifications for Enhanced Small Form Factor Pluggable Module SFP+ Revision 4.1". July 6, 2009. Retrieved September 25, 2023.
- ^ Tektronix (November 2013). "Characterizing an SFP+ Transceiver at the 16G Fibre Channel Rate".
- ^ "Roadmaps". Fibre Channel Industry Association. Retrieved March 5, 2023.
- ^ "10-Gigabit Ethernet camp eyes SFP+". LightWave. April 2006.
- ^ "SFP+ to XENPAK adapter".
- ^ "10GBASE X2 to SFP+ Converter". December 27, 2016.
- ^ "SFP Transceiver".
- ^ Ryan Latchman and Bharat Tailor (January 22, 2008). "The road to SFP+: Examining module and system architectures". Lightwave. Retrieved July 26, 2011.
{{cite web}}: CS1 maint: deprecated archival service (link) - ^ "Ethernet Summit SFP28 examples" (PDF).
- ^ "Cisco SFP28 product examples".
- ^ "SFP28 LR 1310 nm transceivers".
- ^ "SFP28 850 nm example product" (PDF).
- ^ "25GbE SFP28 Active Optical Cable" (PDF). Mellanox. Retrieved October 25, 2018.
- ^ "Intel Ethernet SFP28 Twinaxial Cables" (PDF). Retrieved October 25, 2018.
- ^ "Cisco SFP28 direct attach cables" (PDF).
- ^ "Compact SFP, Compact SFF MSA group forms". Lightwave. February 20, 2008. Retrieved April 12, 2018.
- ^ "Introducing Compact Small Form-Factor Pluggable Module (Compact SFP)". Cisco Systems. Retrieved January 12, 2019.
- ^ http://sfp-dd.com/ SFP-DD MSA
- ^ a b QSFP-DD MSA (July 26, 2022). "QSFP-DD/QSFP-DD800/QSFP112 Hardware Specification for QSFP DOUBLE DENSITY 8X AND QSFP 4X PLUGGABLE TRANSCEIVERS Revision 6.3" (PDF).
- ^ SFF INF-8628
- ^ "QSFP-DD MSA" (PDF). July 25, 2024. Retrieved August 15, 2024.
- ^ a b c d SFF Committee. "QSFP Public Specification (INF-8438)" (PDF). SFF Committee. p. 12. Retrieved June 22, 2016.
- ^ a b SFF Committee. "QSFP+ 10 Gbs 4X Pluggable Transceiver (SFF-8436)" (PDF). p. 13. Retrieved June 22, 2016.
- ^ SFF Committee. "QSFP+ 14 Gb/s 4X Pluggable Transceiver Solution (QSFP14)" (PDF). p. 5. Retrieved June 22, 2016.
- ^ "100G Optics and Cabling Q&A Document" (PDF). www.arista.com. Arista Networks.
- ^ "SFF-8024: Management Interface for Cabled Environments". 4.6. SNIA SFF Committee. February 14, 2019. Retrieved April 4, 2019.
- ^ "Arista 400G Transceivers and Cables: Q&A" (PDF). www.arista.com. Arista Networks, Inc. Retrieved April 4, 2019.
- ^ "Cisco Nexus 5600 specifications".
- ^ "Finisar 4 x 10GbE fanout QSFP".
- ^ "Arista 40Gb port to 4 x 10GbE breakout" (PDF).
- ^ "QSFP28-to-SFP28 breakout".
- ^ "QSFP56 : 4-2334236-1 Pluggable I/O Cable Assemblies". TE Connectivity.
- ^ For Television — Serial Digital Fiber Transmission System for SMPTE 259M, SMPTE 344M, SMPTE 292 and SMPTE 424M Signals. doi:10.5594/SMPTE.ST297.2006. ISBN 978-1-61482-435-0. Archived from the original on September 3, 2017. Retrieved January 15, 2024.
- ^ John Gilmore. "Gigabit Ethernet fiber SFP slots and lock-in". Retrieved December 21, 2010.
- ^ "FLEXBOX SERIES - CONFIGURE UNIVERSAL TRANSCEIVERS". Retrieved September 20, 2019.
- ^ "SFP28 Transceiver, 25G SFP28 Optical Transceiver Module". FS Germany. Retrieved March 28, 2020.
- ^ "Do You Know the CWDM Transceiver Color Code? | Optcore.net". May 31, 2018. Retrieved March 28, 2020.[unreliable source?]
- ^ "Cisco SFP and SFP+ Transceiver Module Installation Notes". Cisco Systems. Retrieved June 26, 2021.
- ^ INF-8074i B4
- ^ "INF-8077i: 10 Gigabit Small Form Factor Pluggable Module" (PDF). Small Form Factor Committee. August 31, 2005. Archived from the original (PDF) on March 17, 2017. Retrieved March 16, 2017.
- ^ SFF INF-8438i 6.2.2 Management Interface Timing Specification
- ^ SFF-8472 (PDF), November 21, 2014, archived from the original (PDF) on March 17, 2017
External links
[edit]
Ethernet family of local area network technologies | |
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