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10 Gigabit Ethernet (10GE, 10GbE, or 10 GigE) is a group of computer networking technologies for transmitting Ethernet frames at a rate of 10 
gigabits per second In telecommunications, data-transfer rate is the average number of bits (bitrate), characters or symbols (baudrate), or data blocks per unit time passing through a communication link in a data-transmission system. Common data rate units are multi ...
. It was first defined by the IEEE 802.3ae-2002 standard. Unlike previous Ethernet standards, 10 Gigabit Ethernet defines only full-duplex point-to-point links which are generally connected by network switches; shared-medium
CSMA/CD Carrier-sense multiple access with collision detection (CSMA/CD) is a medium access control (MAC) method used most notably in early Ethernet technology for local area networking. It uses carrier-sensing to defer transmissions until no other statio ...
operation has not been carried over from the previous generations Ethernet standards so half-duplex operation and repeater hubs do not exist in 10GbE. The 10 Gigabit Ethernet standard encompasses a number of different
physical layer In the seven-layer OSI model of computer networking, the physical layer or layer 1 is the first and lowest layer; The layer most closely associated with the physical connection between devices. This layer may be implemented by a PHY chip. The ...
(PHY) standards. A networking device, such as a switch or a network interface controller may have different PHY types through pluggable PHY modules, such as those based on SFP+. Like previous versions of Ethernet, 10GbE can use either copper or fiber cabling. Maximum distance over copper cable is 100 meters but because of its bandwidth requirements, higher-grade cables are required. The adoption of 10 Gigabit Ethernet has been more gradual than previous revisions of Ethernet: in 2007, one million 10GbE ports were shipped, in 2009 two million ports were shipped, and in 2010 over three million ports were shipped, with an estimated nine million ports in 2011. , although the price per gigabit of bandwidth for 10 Gigabit Ethernet was about one-third compared to Gigabit Ethernet, the price per port of 10 Gigabit Ethernet still hindered more widespread adoption.


Standards

Over the years the
Institute of Electrical and Electronics Engineers The Institute of Electrical and Electronics Engineers (IEEE) is a 501(c)(3) professional association for electronic engineering and electrical engineering (and associated disciplines) with its corporate office in New York City and its operation ...
(IEEE) 802.3 working group has published several standards relating to 10GbE.


Physical layer modules

To implement different 10GbE physical layer standards, many interfaces consist of a standard socket into which different physical (PHY) layer modules may be plugged. PHY modules are not specified in an official standards body but by multi-source agreements (MSAs) that can be negotiated more quickly. Relevant MSAs for 10GbE include XENPAK (and related X2 and XPAK),
XFP The XFP (10 gigabit small form-factor pluggable) is a standard for transceivers for high-speed computer network and telecommunication links that use optical fiber. It was defined by an industry group in 2002, along with its interface to other e ...
and SFP+. When choosing a PHY module, a designer considers cost, reach, media type, power consumption, and size (form factor). A single point-to-point link can have different MSA pluggable formats on either end (e.g. XPAK and SFP+) as long as the 10GbE optical or copper port type (e.g. 10GBASE-SR) supported by the pluggable is identical. XENPAK was the first MSA for 10GE and had the largest form factor. X2 and XPAK were later competing standards with smaller form factors. X2 and XPAK have not been as successful in the market as XENPAK. XFP came after X2 and XPAK and it is also smaller. The newest module standard is the enhanced small form-factor pluggable transceiver, generally called SFP+. Based on the small form-factor pluggable transceiver (SFP) and developed by the ANSI T11
fibre channel Fibre Channel (FC) is a high-speed data transfer protocol providing in-order, lossless delivery of raw block data. Fibre Channel is primarily used to connect computer data storage to servers in storage area networks (SAN) in commercial data cen ...
group, it is smaller still and lower power than XFP. SFP+ has become the most popular socket on 10GE systems. SFP+ modules do only optical to electrical conversion, no clock and data recovery, putting a higher burden on the host's channel equalization. SFP+ modules share a common physical form factor with legacy SFP modules, allowing higher port density than XFP and the re-use of existing designs for 24 or 48 ports in a
19-inch rack A 19-inch rack is a standardized frame or enclosure for mounting multiple electronic equipment modules. Each module has a front panel that is wide. The 19 inch dimension includes the edges or "ears" that protrude from each side of the equ ...
width blade. Optical modules are connected to a host by either a XAUI, XFI or SerDes Framer Interface (SFI) interface. XENPAK, X2, and XPAK modules use XAUI to connect to their hosts. XAUI (XGXS) uses a four-lane data channel and is specified in IEEE 802.3 Clause 47. XFP modules use a XFI interface and SFP+ modules use an SFI interface. XFI and SFI use a single lane data channel and the 64b/66b encoding specified in IEEE 802.3 Clause 49. SFP+ modules can further be grouped into two types of host interfaces: linear or limiting. Limiting modules are preferred except when for long-reach applications using 10GBASE-LRM modules.


Optical fiber

There are two basic types of optical fiber used for 10 Gigabit Ethernet: single-mode (SMF) and multi-mode (MMF). In SMF light follows a single path through the fiber while in MMF it takes multiple paths resulting in differential mode delay (DMD). SMF is used for long-distance communication and MMF is used for distances of less than 300 m. SMF has a narrower core (8.3 μm) which requires a more precise termination and connection method. MMF has a wider core (50 or 62.5 μm). The advantage of MMF is that it can be driven by a low cost Vertical-cavity surface-emitting laser (VCSEL) for short distances, and multi-mode connectors are cheaper and easier to terminate reliably in the field. The advantage of SMF is that it can work over longer distances. In the 802.3 standard, reference is made to FDDI-grade MMF fiber. This has a 62.5 μm core and a minimum modal bandwidth of 160 MHz·km at 850 nm. It was originally installed in the early 1990s for FDDI and
100BASE-FX In computer networking, Fast Ethernet physical layers carry traffic at the nominal rate of 100 Mbit/s. The prior Ethernet speed was 10 Mbit/s. Of the Fast Ethernet physical layers, 100BASE-TX is by far the most common. Fast Ethern ...
networks. The 802.3 standard also references ISO/IEC 11801 which specifies optical MMF fiber types OM1, OM2, OM3 and OM4. OM1 has a 62.5 μm core while the others have a 50 μm core. At 850 nm the minimum modal bandwidth of OM1 is 200 MHz·km, of OM2 500 MHz·km, of OM3 2000 MHz·km and of OM4 4700 MHz·km. FDDI-grade cable is now obsolete and new
structured cabling In telecommunications, structured cabling is building or campus cabling infrastructure that consists of a number of standardized smaller elements (hence structured) called subsystems. Structured cabling components include twisted pair and opti ...
installations use either OM3 or OM4 cabling. OM3 cable can carry 10 Gigabit Ethernet 300 meters using low cost 10GBASE-SR optics. OM4 can manage 400 meters. To distinguish SMF from MMF cables, SMF cables are usually yellow, while MMF cables are orange (OM1 & OM2) or aqua (OM3 & OM4). However, in fiber optics there is no uniform color for any specific optical speed or technology with the exception being angular physical connector (APC), it being an agreed color of green. There are also
active optical cable Active may refer to: Music * ''Active'' (album), a 1992 album by Casiopea * Active Records, a record label Ships * ''Active'' (ship), several commercial ships by that name * HMS ''Active'', the name of various ships of the British Royal ...
s (AOC). These have the optical electronics already connected eliminating the connectors between the cable and the optical module. They plug into standard SFP+ sockets. They are lower cost than other optical solutions because the manufacturer can match the electronics to the required length and type of cable.


10GBASE-SR

10GBASE-SR ("short range") is a port type for
multi-mode fiber Multi-mode optical fiber is a type of optical fiber mostly used for communication over short distances, such as within a building or on a campus. Multi-mode links can be used for data rates up to 100 Gbit/s. Multi-mode fiber has a fairly large ...
and uses 850 nm lasers. Its Physical Coding Sublayer (PCS) is 64b/66b and is defined in IEEE 802.3 Clause 49 and its
Physical Medium Dependent Physical medium dependent sublayers or PMDs further help to define the physical layer of computer network protocols. They define the details of transmission and reception of individual bits on a physical medium. These responsibilities encompass b ...
(PMD) sublayer in Clause 52. It delivers serialized data at a line rate of 10.3125 Gbd.IEEE 802.3 ''52.1.1.1.2 PMD_UNITDATA.request: When generated'' The range depends on the type of multi-mode fiber used. MMF has the advantage over SMF of having lower cost connectors; its wider core requires less mechanical precision. The 10GBASE-SR transmitter is implemented with a VCSEL which is low cost and low power. OM3 and OM4 optical cabling is sometimes described as ''laser optimized'' because they have been designed to work with VCSELs. 10GBASE-SR delivers the lowest cost, lowest power and smallest form factor optical modules. There is a lower cost, lower power variant sometimes referred to as 10GBASE-SRL (10GBASE-SR lite). This is inter-operable with 10GBASE-SR but only has a reach of 100 meters.


10GBASE-LR

10GBASE-LR (long reach) is a port type for single-mode fiber and uses 1310 nm lasers. Its 64b/66b PCS is defined in IEEE 802.3 Clause 49 and its PMD sublayer in Clause 52. It delivers serialized data at a line rate of 10.3125 GBd. The 10GBASE-LR transmitter is implemented with a Fabry–Pérot or
Distributed feedback laser A distributed-feedback laser (DFB) is a type of laser diode, quantum-cascade laser or optical-fiber laser where the active region of the device contains a periodically structured element or diffraction grating. The structure builds a one-dimensio ...
(DFB). DFB lasers are more expensive than VCSELs but their high power and longer wavelength allow efficient coupling into the small core of single-mode fiber over greater distances. 10GBASE-LR maximum fiber length is 10 kilometers, although this will vary depending on the type of single-mode fiber used.


10GBASE-LRM

10GBASE-LRM, (long reach multi-mode) originally specified in IEEE 802.3aq is a port type for multi-mode fiber and uses 1310 nm lasers. Its 64b/66b PCS is defined in IEEE 802.3 Clause 49 and its PMD sublayer in Clause 68. It delivers serialized data at a line rate of 10.3125 GBd. 10GBASE-LRM uses electronic dispersion compensation (EDC) for receive equalization. 10GBASE-LRM allows distances up to on FDDI-grade multi-mode fiber and the same 220m maximum reach on OM1, OM2 and OM3 fiber types. 10GBASE-LRM reach is not quite as far as the older 10GBASE-LX4 standard. Some 10GBASE-LRM transceivers also allow distances up to on standard single-mode fiber (SMF, G.652), however this is not part of the IEEE or MSA specification. To ensure that specifications are met over FDDI-grade, OM1 and OM2 fibers, the transmitter should be coupled through a mode conditioning patch cord. No mode conditioning patch cord is required for applications over OM3 or OM4.


10GBASE-ER

10GBASE-ER (extended reach) is a port type for single-mode fiber and uses 1550 nm lasers. Its 64b/66b PCS is defined in IEEE 802.3 Clause 49 and its PMD sublayer in Clause 52. It delivers serialized data at a line rate of 10.3125 GBd. The 10GBASE-ER transmitter is implemented with an externally modulated laser (EML). 10GBASE-ER has a reach of over engineered links and 30 km over standard links.


10GBASE-ZR

Several manufacturers have introduced range under the name 10GBASE-ZR. This 80 km PHY is not specified within the IEEE 802.3ae standard and manufacturers have created their own specifications based upon the 80 km PHY described in the OC-192/ STM-64
SDH SDH may refer to: Science, medicine and technology * Serine dehydratase, an enzyme * L-sorbose 1-dehydrogenase, an enzyme * Succinate dehydrogenase, an enzyme * Shubnikov–de Haas effect * Social Determinants of Health, economic and social condi ...
/ SONET specifications.


10GBASE-LX4

10GBASE-LX4 is a port type for multi-mode fiber and single-mode fiber. It uses four separate laser sources operating at 3.125 Gbit/s and
Coarse wavelength-division multiplexing In fiber-optic communications, wavelength-division multiplexing (WDM) is a technology which multiplexes a number of optical carrier signals onto a single optical fiber by using different wavelengths (i.e., colors) of laser light. This techniq ...
with four unique wavelengths around 1310 nm. Its 8b/10b PCS is defined in IEEE 802.3 Clause 48 and its
Physical Medium Dependent Physical medium dependent sublayers or PMDs further help to define the physical layer of computer network protocols. They define the details of transmission and reception of individual bits on a physical medium. These responsibilities encompass b ...
(PMD) sublayer in Clause 53. 10GBASE-LX4 has a range of over SMF. It can reach over FDDI-grade, OM1, OM2 and OM3 multi-mode cabling. In this case, it needs to be coupled through a SMF offset-launch
mode-conditioning patch cord A fiber-optic patch cord is a fiber-optic cable capped at either end with connectors that allow it to be rapidly and conveniently connected to CATV, an optical switch or other telecommunication equipment. Its thick layer of protection is used ...
.


10GBASE-PR

10GBASE-PR originally specified in IEEE
802.3av The 10 Gbit/s Ethernet Passive Optical Network standard, better known as 10G-EPON allows computer network connections over telecommunication provider infrastructure. The standard supports two configurations: ''symmetric'', operating at 10 Gbit/s d ...
is a 10 Gigabit Ethernet PHY for passive optical networks and uses 1577 nm lasers in the downstream direction and 1270 nm lasers in the upstream direction. Its PMD sublayer is specified in Clause 75. Downstream delivers serialized data at a line rate of 10.3125 Gbit/s in a point to multi-point configuration. 10GBASE-PR has three power budgets specified as 10GBASE-PR10, 10GBASE-PR20 and 10GBASE-PR30.


10GBASE-BR

Multiple vendors introduced single strand, bi-directional 10 Gbit/s optics capable of a
single-mode fiber A transverse mode of electromagnetic radiation is a particular electromagnetic field pattern of the radiation in the plane perpendicular (i.e., transverse) to the radiation's propagation direction. Transverse modes occur in radio waves and microwav ...
connection functionally equivalent to 10GBASE-LR or -ER, but using a single strand of fiber optic cable. Analogous to
1000BASE-BX10 In computer networking, Gigabit Ethernet (GbE or 1 GigE) is the term applied to transmitting Ethernet frames at a rate of a gigabit per second. The most popular variant, 1000BASE-T, is defined by the IEEE 802.3ab standard. It came into use i ...
, this is accomplished using a passive prism inside each optical transceiver and a matched pair of transceivers using two different wavelengths such as 1270 and 1330 nm. Modules are available in varying transmit powers and reach distances ranging from 10 to 80 km. These advances were subsequently standardized in IEEE 802.3cp-2021 with reaches of 10, 20, or 40 km.


Copper

10 Gigabit Ethernet can also run over twin-axial cabling, twisted pair cabling, and backplanes.


10GBASE-CX4

SFF-8470 connector 10GBASE-CX4 was the first 10 Gigabit copper standard published by 802.3 (as 802.3ak-2004). It uses the XAUI 4-lane PCS (Clause 48) and copper cabling similar to that used by InfiniBand technology with the same SFF-8470 connectors. It is specified to work up to a distance of . Each lane carries 3.125 GBd of signaling bandwidth. 10GBASE-CX4 has been used for stacking switches. It offers the advantages of low power, low cost and low latency, but has a bigger form factor and more bulky cables than the newer single-lane SFP+ standard, and a much shorter reach than fiber or 10GBASE-T. This cable is fairly rigid and considerably more costly than Category 5/6 UTP or fiber. 10GBASE-CX4 applications are now commonly achieved using SFP+ Direct Attach and , shipments of 10GBASE-CX4 have been very low.


SFP+ direct attach

Also known as direct attach (DA), direct attach copper (DAC), 10GSFP+Cu, 10GBASE-CR or 10GBASE-CX1. Short direct attach cables use a passive twinaxial cabling assembly while longer ones, sometimes called ''active optical cable'' (AOC) use short wavelength optics. Both types connect directly into an SFP+ housing. SFP+ direct attach has a fixed-length cable, up to 15 m for copper cables, or up to 100 m in for AOC. Like 10GBASE-CX4, DA is low-power, low-cost and low-latency with the added advantages of using less bulky cables and of having the small SFP+ form factor. SFP+ direct attach today is tremendously popular, with more ports installed than 10GBASE-SR.


Backplane

Backplane Ethernet, also known by the name of the task force that developed it, 802.3ap, is used in backplane applications such as blade servers and modular network equipment with upgradable line cards. 802.3ap implementations are required to operate over up to of copper printed circuit board with two connectors. The standard defines two port types for 10 Gbit/s (10GBASE-KX4 and 10GBASE-KR) and a single 1 Gbit/s port type (1000BASE-KX). It also defines an optional layer for
forward error correction In computing, telecommunication, information theory, and coding theory, an error correction code, sometimes error correcting code, (ECC) is used for controlling errors in data over unreliable or noisy communication channels. The central idea is ...
, a backplane autonegotiation protocol and link training for 10GBASE-KR where the receiver tunes a three-tap transmit equalizer. The autonegotiation protocol selects between 1000BASE-KX, 10GBASE-KX4, 10GBASE-KR or 40GBASE-KR4 operation.


10GBASE-KX4

This operates over four backplane lanes and uses the same physical layer coding (defined in IEEE 802.3 Clause 48) as 10GBASE-CX4.


10GBASE-KR

This operates over a single backplane lane and uses the same physical layer coding (defined in IEEE 802.3 Clause 49) as 10GBASE-LR/ER/SR. New backplane designs use 10GBASE-KR rather than 10GBASE-KX4.


10GBASE-T

10GBASE-T, or IEEE 802.3an-2006, is a standard released in 2006 to provide 10 Gbit/s connections over unshielded or shielded twisted pair cables, over distances up to . Category 6A is required to reach the full distance and category 5e or 6 may reach up to depending on the quality of installation. 10GBASE-T cable infrastructure can also be used for 1000BASE-T allowing a gradual upgrade from 1000BASE-T using
autonegotiation Autonegotiation is a signaling mechanism and procedure used by Ethernet over twisted pair by which two connected devices choose common transmission parameters, such as speed, duplex mode, and flow control. In this process, the connected devices ...
to select which speed is used. Due to additional line coding overhead, 10GBASE-T has a slightly higher latency (2 to 4 microseconds) in comparison to most other 10GBASE variants (1 microsecond or less). In comparison, 1000BASE-T latency is 1 to 12 microseconds (depending on packet size). 10GBASE-T uses the IEC 60603-7
8P8C A modular connector is a type of electrical connector for cords and cables of electronic devices and appliances, such as in computer networking, telecommunication equipment, and audio headsets. Modular connectors were originally developed for ...
modular connectors already widely used with Ethernet. Transmission characteristics are now specified to . To reach this frequency
Category 6A Category 6 cable (Cat 6) is a standardized twisted pair cable for Ethernet and other network physical layers that is backward compatible with the Category 5/5e and Category 3 cable standards. Cat 6 must meet more stringent s ...
or better balanced twisted pair cables specified in ISO/IEC 11801 amendment 2 or ANSI/TIA-568-C.2 are needed to carry 10GBASE-T up to distances of 100 m. Category 6 cables can carry 10GBASE-T for shorter distances when qualified according to the guidelines in ISO TR 24750 or TIA-155-A. The 802.3an standard specifies the wire-level modulation for 10GBASE-T to use
Tomlinson-Harashima precoding In telecommunications, dirty paper coding (DPC) or Costa precoding is a technique for efficient transmission of digital data through a channel subjected to some interference known to the transmitter. The technique consists of precoding the data in o ...
(THP) and pulse-amplitude modulation with 16 discrete levels (PAM-16), encoded in a two-dimensional checkerboard pattern known as DSQ128 sent on the line at 800 Msymbols/sec. Prior to precoding,
forward error correction In computing, telecommunication, information theory, and coding theory, an error correction code, sometimes error correcting code, (ECC) is used for controlling errors in data over unreliable or noisy communication channels. The central idea is ...
(FEC) coding is performed using a 048,1723sub>2
low-density parity-check code In information theory, a low-density parity-check (LDPC) code is a linear error correcting code, a method of transmitting a message over a noisy transmission channel. An LDPC code is constructed using a sparse Tanner graph (subclass of the bipa ...
on 1723 bits, with the parity check matrix construction based on a generalized Reed–Solomon
2,2,31 The comma is a punctuation mark that appears in several variants in different languages. It has the same shape as an apostrophe or single closing quotation mark () in many typefaces, but it differs from them in being placed on the baseline o ...
code over GF(26). Another 1536 bits are uncoded. Within each 1723+1536 block, there are 1+50+8+1 signaling and error detection bits and 3200 data bits (and occupy 320 ns on the line). In contrast, PAM-5 is the modulation technique used in 1000BASE-T Gigabit Ethernet. The line encoding used by 10GBASE-T is the basis for the newer and slower 2.5GBASE-T and 5GBASE-T standard, implementing a 2.5 or 5.0 Gbit/s connection over existing category 5e or 6 cabling. Cables that will not function reliably with 10GBASE-T may successfully operate with 2.5GBASE-T or 5GBASE-T if supported by both ends.


10GBASE-T1

10GBASE-T1 is for automotive applications and operates over a single balanced pair of conductors up to 15 m long, and is standardized in 802.3ch-2020.


WAN PHY (10GBASE-W)

At the time that the 10 Gigabit Ethernet standard was developed, interest in 10GbE as a wide area network (WAN) transport led to the introduction of a WAN PHY for 10GbE. The WAN PHY was designed to interoperate with OC-192/STM-64 SDH/SONET equipment using a light-weight SDH/SONET frame running at 9.953 Gbit/s. The WAN PHY operates at a slightly slower data-rate than the local area network (LAN) PHY. The WAN PHY can drive maximum link distances up to 80 km depending on the fiber standard employed. The WAN PHY uses the same 10GBASE-S, 10GBASE-L and 10GBASE-E optical PMDs as the LAN PHYs and is designated as 10GBASE-SW, 10GBASE-LW or 10GBASE-EW. Its 64b/66b PCS is defined in IEEE 802.3 clause 49 and its PMD sublayers in clause 52. It also uses a WAN interface sublayer (WIS) defined in clause 50 which adds extra encapsulation to format the frame data to be compatible with SONET STS-192c.


Notes


See also

* GG45 *
List of interface bit rates This is a list of interface bit rates, is a measure of information transfer rates, or digital bandwidth capacity, at which digital interfaces in a computer or network can communicate over various kinds of buses and channels. The distinction can ...
*
Optical communication Optical communication, also known as optical telecommunication, is communication at a distance using light to carry information. It can be performed visually or by using electronic devices. The earliest basic forms of optical communication date b ...
* Optical fiber cable *
Parallel optical interface A parallel optical interface is a form of fiber optic technology aimed primarily at communications and networking over relatively short distances (less than 300 meters), and at high bandwidths. Parallel optic interfaces differ from traditional fi ...
*
TERA TERA is a shielded twisted pair connector for use with Category 7 twisted-pair data cables, developed by The Siemon Company and standardised in 2003 by the International Electrotechnical Commission (IEC) with the reference IEC 61076-3-104. The ...
* XAUI


References

*


External links


Ethernet Alliance website

World's First Independent 10GBASE-T Comparative Test Study
{{Ethernet Ethernet standards