View source for Gigabit Ethernet

{{Short description|Standard for Ethernet networking at a data rate of 1 gigabit per second}}
{{Redirect|GigE|the camera protocol|GigE vision}}
{{Use American English|date=September 2025}}
{{Use mdy dates|date=September 2025}}

[[File:Intel PRO-1000 GT PCI NIC.jpg|thumb|Intel PRO/1000 GT [[Peripheral Component Interconnect|PCI]] [[network interface controller]]]]

In [[computer network]]ing, '''Gigabit Ethernet''' ('''GbE''' or '''1 GigE''') is the term applied to transmitting [[Ethernet frame]]s 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 in 1999, and has replaced [[Fast Ethernet]] in wired local networks due to its considerable speed improvement over Fast Ethernet, as well as its use of cables and equipment that are widely available, economical, and similar to previous standards. The first standard for faster [[10 Gigabit Ethernet]] was approved in 2002.<ref>{{cite web |url=http://www.ieee802.org/3/ae/index.html |title=IEEE P802.3ae 10Gb/s Ethernet Task Force |access-date=March 19, 2013 }}</ref>

== History ==
[[Ethernet]] was the result of research conducted at [[Xerox PARC]] in the early 1970s, and later evolved into a widely implemented [[Physical layer|physical]] and [[Data link layer|link layer]] protocol. [[Fast Ethernet]] increased the speed from 10 to 100 megabits per second ({{nowrap|Mbit/s}}). Gigabit Ethernet was the next iteration, increasing the speed to {{nowrap|1000 Mbit/s}}.

The initial standard for Gigabit Ethernet was produced by the [[IEEE]] in June 1998 as '''IEEE 802.3z''', and required [[optical fiber]]. 802.3z is commonly referred to as 1000BASE-X, where -X refers to either -CX, -SX, -LX, or (non-standard) -ZX.{{efn|For the history behind the "X" see {{section link|Fast Ethernet|Nomenclature}}.}} IEEE 802.3ab, ratified in 1999, defines Gigabit Ethernet transmission over [[unshielded twisted pair]] (UTP) [[Category 5 cable|category 5, 5e]] or [[Category 6 cable|6]] cabling, and became known as 1000BASE-T. With the ratification of 802.3ab, Gigabit Ethernet became a desktop technology as organizations could use their existing copper cabling infrastructure. [[IEEE 802.3ah]], ratified in 2004, added two more GbE fiber standards: 1000BASE-LX10 (which was already widely implemented as vendor-specific extension) and 1000BASE-BX10. This was part of a larger group of protocols known as [[Ethernet in the first mile]].

Initially, Gigabit Ethernet was deployed in high-capacity [[backbone network]] links (for instance, on a high-capacity campus network). In 2000 and 2001, [[Apple Computer|Apple's]] [[Power Mac G4]] and [[PowerBook G4]] respectively were the first mass-produced personal computers to feature the 1000BASE-T connection.<ref>{{Cite web|url=http://www.apple-history.com/frames/body.php?page=gallery&model=g4giga |title=Power Macintosh G4 (Gigabit Ethernet) |publisher=apple-history.com |access-date=November 5, 2007 }}</ref> It quickly became a built-in feature in many other computers.

[[Half-duplex]] GbE links connected through [[Ethernet hub|repeater hubs]] were part of the IEEE specification,<ref>A single repeater per collision domain is defined in IEEE 802.3 2008 Section 3: 41. Repeater for 1000&nbsp;Mb/s baseband networks</ref> but the specification has not been maintained and [[full-duplex]] operation with [[Network switch|switches]] is, in practice, used exclusively.

== Varieties ==
[[File:Intelpromtserverpcixadapter1000mta342.jpg|thumb|1000BASE-T–capable [[network interface card]] made by [[Intel]], which connects to a computer via [[PCI-X]]]]

There are five [[physical layer]] standards for Gigabit Ethernet using [[optical fiber]] (1000BASE-X), [[twisted pair cable]] (1000BASE-T), or shielded [[Balanced line|balanced]] copper cable (1000BASE-CX).

The IEEE 802.3z standard includes 1000BASE-SX for transmission over [[multi-mode fiber]], 1000BASE-LX for transmission over [[single-mode fiber]], and the nearly obsolete 1000BASE-CX for transmission over shielded balanced copper cabling. These standards use [[8b/10b encoding]], which adds a 25% overhead,{{efn|A {{nowrap|1250 Mbit/s}} line rate is required to achieve the {{nowrap|1000 Mbit/s}} performance}} to ensure a [[DC balance]]d signal and allow for clock recovery. The symbols are then sent using [[NRZ line code]].

Optical fiber transceivers are most often implemented as user-swappable modules in [[Small Form-factor Pluggable|SFP]] form or [[GBIC]] on older devices.

IEEE 802.3ab, which defines the widely used 1000BASE-T interface type, uses a different encoding scheme in order to keep the symbol rate as low as possible, allowing transmission over twisted pair.

IEEE 802.3ap defines Ethernet operation over [[electrical backplane]]s at different speeds.

Ethernet in the first mile later added 1000BASE-LX10 and -BX10 extended-distance fiber-optic variants.

== Copper ==
{| class="wikitable" style="line-height:110%;"
|+ Comparison of [[Ethernet over twisted pair|twisted-pair-based Ethernet]] physical transport layers (TP-PHYs)<ref name="TDG_ETH_2nd" /><!--Ref "TDG_ETH_2nd" is defined in [[Template:Fibre legend]].-->
|-
! Name
! Standard
! Status
! Speed {{nowrap|(Mbit/s)}}
! Pairs required
! Lanes per direction
! Bits per hertz
! [[Line code]]
! [[Symbol rate]] per lane (MBd) 
! Bandwidth (MHz)
! Max distance (m)
! Cable (minimum required)
! Cable rating (MHz)
! Usage
|-
| {{nowrap|[[#1000BASE‑T|1000BASE‑T]]}}
| {{nowrap|802.3ab-1999}} (CL40)
| {{active|current}}
| align="right" | 1000
| align="right" | 4
| align="right" | 4
| align="right" | 4
| align="right" | TCM 4D-PAM-5
| align="right" | 125
| align="right" | 62.5
| align="right" | 100
| align="center" | [[Cat&nbsp;5]]
| align="right" | 100
| align="center" | LAN
|-
| {{nowrap|[[#1000BASE-T1|1000BASE-T1]]}}
| {{nowrap|802.3bp-2016}}
| {{active|current}}
| align="right" | 1000
| align="right" | 1
| align="right" | 1
| align="right" | 2.6{{overline|6}}
| align="right" | PAM-3 80B/81B RS-FEC
| align="right" | 750
| align="right" | 375
| align="right" | 40
| align="center" | [[Cat&nbsp;6A]]
| align="right" | 500
| align="center" | Automotive, IoT, M2M
|-
| {{nowrap|[[#1000BASE-TX|1000BASE‑TX]]}}
| {{nowrap|TIA/EIA-854}} (2001)
| {{N/A|obsolete}}
| align="right" | 1000
| align="right" | 4
| align="right" | 2
| align="right" | 4
| align="right" | PAM-5
| align="right" | 250
| align="right" | 125
| align="right" | 100
| align="center" | [[Cat&nbsp;6]]
| align="right" | 250
| {{N/A|''Market failure''}}
|}

===1000BASE-T===
[[File:Supermicro AOC-SGP-I2 Gigabit Ethernet NIC, PCI-Express x4 card.jpg|thumb|[[Supermicro]] AOC-SGP-I2 dual-port Gigabit Ethernet [[Network interface controller|NIC]], a [[PCI Express]] ×&nbsp;4 card]]

IEEE 802.3ab is the original standard for Gigabit Ethernet over twisted-pair wiring, known as 1000BASE-T.

Each 1000BASE-T network segment is recommended to be a maximum length of {{convert|100|m|ft|abbr=off|sp=us}},<ref>{{cite video |last=Barrera |first=Dan |title=Interview: Dan Barrera With Ideal Networks About TIA 42 Cabling Standards & Testing Processes |url=https://www.youtube.com/watch?v=kNa_IdfivKs |archive-url=https://ghostarchive.org/varchive/youtube/20211117/kNa_IdfivKs |archive-date=November 17, 2021 |url-status=live |website=Youtube |access-date=April 8, 2020 |time=11:49 }}{{cbignore}}</ref>{{efn|In ISO the length is purely informative. The length is not a pass/fail criterion as testing the conformance to EN 50173 series standards.}} and must use [[Category 5 cable]] or better.

[[Autonegotiation]] is a requirement for 1000BASE-T implementations<ref>,{{Cite web |url=http://standards.ieee.org/reading/ieee/interp/IEEE802.3af-2003interp-6.pdf |archive-url=https://web.archive.org/web/20060130134410/http://standards.ieee.org/reading/ieee/interp/IEEE802.3af-2003interp-6.pdf |archive-date=January 30, 2006 |title=Auto-Negotiation; 802.3-2002 |work=IEEE Standards Interpretations |publisher=IEEE }}</ref><ref>{{Cite web|author=IEEE |url=https://standards.ieee.org/wp-content/uploads/import/download/802.3-2008_downloads.zip |title=Part 3: Carrier Sense Multiple Access with Collision Detection (CSMA/CD) access method and Physical Layer specifications |publisher=SECTION TWO: This section includes Clause21 through Clause 33 and Annex 22A through Annex 33E.|access-date=February 18, 2010 }}</ref> as minimally the clock source for the link has to be negotiated, as one endpoint must be master and the other endpoint must be slave.

In a departure from both [[10BASE-T]] and [[100BASE-TX]], which use a cable pair in each direction, 1000BASE-T uses four cable pairs for simultaneous transmission in both directions through the use of [[echo cancellation]] with [[adaptive equalization]], the resulting circuits being called ''hybrid circuits''<ref>{{Cite web |publisher=IEEE |url=http://standards.ieee.org/getieee802/download/802.3-2008_section1.pdf |title=1.4 Definitions 1.4.187 hybrid |archive-url=https://web.archive.org/web/20101206030247/http://standards.ieee.org/getieee802/download/802.3-2008_section1.pdf |archive-date=December 6, 2010 |url-status=live}}</ref> as used in [[telephone hybrid]]s. Line coding is five-level [[pulse-amplitude modulation]] (PAM-5). The symbol rate is identical to that of 100BASE-TX (125&nbsp;[[megabaud]]) and the noise immunity of the five-level signaling is also identical to that of the three-level signaling in 100BASE-TX, since 1000BASE-T uses four-dimensional [[trellis coded modulation]] (TCM) to achieve a 6&nbsp;[[Decibel|dB]] [[coding gain]] across the four pairs.

Since autonegotiation takes place on only two pairs, if two 1000BASE-T interfaces are connected through a cable with only two pairs, the interfaces will complete negotiation and choose gigabit as the best common operating mode, but the link will never come up because, in most cases,{{efn|Some implementations offer an Ethernet@Wirespeed option where a two-pair connection leads to a slower yet functional link.<ref>{{Cite web |url=https://www.broadcom.com/application/ethernet_nic.php |title=Broadcom Ethernet NIC FAQs |access-date=April 25, 2016 }}</ref>}} all four pairs are required for data communications. Most 1000BASE-T implementations have a specific register to diagnose this behavior. 

The data is transmitted over four pairs, eight [[bit]]s at a time. First, eight bits of data are expanded into four three-bit symbols through a [[Scrambler|scrambling procedure]] based on a [[linear-feedback shift register]]; this is similar to what is done in [[100BASE-T2]], but uses different parameters. The three-bit symbols are then mapped to voltage levels that vary continuously during transmission. An example mapping is as follows:

{| class="wikitable" style="text-align: center;"
|-
! Symbol 
| 000 || 001 || 010 || 011 || 100 || 101 || 110 || 111
|-
! Line signal level
| 0 || +1 || +2 || −1 || 0 || +1 || −2 || −1
|}<!--[[User:Kvng/RTH]]-->

''[[Auto-MDIX|Automatic MDI/MDI-X Configuration]]'' is specified as an optional feature in the 1000BASE-T standard,<ref>Clause 40.4.4 in [[IEEE 802.3-2008]]</ref> meaning that straight-through cables will often work between two GbE-capable network node interfaces (both MDI) and between two switch or hub interfaces (both MDI-X). This feature eliminates the need for [[Ethernet crossover cable|crossover cables]], making obsolete the uplink vs normal port choices and manual selector switches found on many older hubs and switches and greatly reduces installation errors.

In order to extend and maximize the use of existing Cat-5e and Cat-6 cabling, the newer standards [[2.5GBASE-T and 5GBASE-T]] operate at 2.5 and {{nowrap|5.0 Gbit/s}}, respectively, on existing copper infrastructure designed for use with 1000BASE-T. They are based on [[10GBASE-T]] but use lower signaling frequencies.

===1000BASE-T1===
{{Broader|Ethernet over twisted pair#Single-pair}}

IEEE 802.3 standardized 1000BASE-T1 in IEEE Std 802.3bp-2016.<ref>{{Cite web|url=http://www.ieee802.org/3/bp/ |title=IEEE P802.3bp 1000BASE-T1 PHY Task Force |publisher=IEEE 802.3 |date=July 29, 2016 |access-date=October 6, 2016 }}</ref> It defines Gigabit Ethernet over a single twisted pair for automotive and industrial applications. It includes cable specifications for 15&nbsp;meters (type&nbsp;A) or 40&nbsp;meters (type&nbsp;B) reach. The transmission is done using PAM-3 at 750 [[megabaud|MBd]].

===1000BASE-TX===
In 2001, the [[Telecommunications Industry Association]] (TIA) created and promoted a standard similar to 1000BASE-T that was simpler to implement, calling it 1000BASE-TX (TIA/EIA-854).<ref>{{cite press release |date=July 25, 2001 |url=http://www.tiaonline.org/news_events/press_room/press_releases/legacy.cfm?parelease=01-87 |title=TIA Publishes New Standard TIA/EIA-854 |publisher=TAI |archive-url=https://web.archive.org/web/20110927060633/http://www.tiaonline.org/news_events/press_room/press_releases/legacy.cfm?parelease=01-87 |archive-date=September 27, 2011 }}</ref> The simplified design would have, in theory, reduced the cost of the required electronics by only using four unidirectional pairs (two pairs TX and two pairs RX) instead of four bidirectional pairs.

===1000BASE-CX===
802.3z-1998 CL39 standardized 1000BASE-CX is an initial standard for Gigabit Ethernet connections with maximum distances of 25 meters using balanced shielded twisted pair and either [[DE-9]] or [[8P8C]] connector (with a pinout different from 1000BASE-T). The short segment length is due to a very high signal transmission rate. Although it is still used for specific applications where cabling is done by IT professionals, for instance, the IBM BladeCenter uses 1000BASE-CX for the Ethernet connections between the blade servers and the switch modules, 1000BASE-T has succeeded it for general copper wiring use.<ref>{{cite web |url=http://www.thenetworkencyclopedia.com/entry/1000basecx/ |title=1000BaseCX |website=The Network Encyclopedia |date=August 17, 2019 |publisher=Ciberforma Lda }}</ref>

===1000BASE-KX===
802.3ap-2007 CL70 standardized 1000BASE-KX as part of the IEEE 802.3ap standard for Ethernet Operation over Electrical Backplanes. This standard defines one to four lanes of backplane links, one RX and one TX differential pair per lane, at link bandwidth ranging from 100&nbsp;Mbit to 10&nbsp;Gbit per second (from 100BASE-KX to 10GBASE-KX4). The 1000BASE-KX variant uses 1.25 [[Gigabaud|GBd]] electrical (not optical) signaling speed.
<!-- |-
| [[Gigabit Ethernet#1000BASE-CX|1000BASE<br />‑CX]]
| {{nowrap|802.3z-1998<br /><small>(CL39)</small>}}
| {{partial|legacy}}
| {{terminated|[[Twisted pair|TWP]]<br />shielded<br />[[balanced]]}}<br />(150&nbsp;Ω)
| {{terminated|<small>[[Modular connector#8P8C (8 position 8 contact)|8P8C]]<br />[[D-subminiature|DE-9]]<br/>[[Fibre Channel electrical interface#8-pin "HSSDC" cable connector (High Speed Serial Data Connection)|FC/HSSDC]]<br />{{nowrap|CX4 (SFF-8470)}}<br />{{nowrap|(IEC 61076-3-103)}}</small>}}
| {{N/A}}
| align="right" | 0.025
| align="right" | 4
| align="right" | 4
| <small>[[Data center]]s;<br />predates 1000BASE-T; rarely used.</small>
|-
| [[Gigabit Ethernet#1000BASE-KX|1000BASE<br />‑KX]]
| {{nowrap|802.3ap-2007<br /><small>(CL70)</small>}}
| {{active|current}}
| {{terminated|Cu-[[Backplane]]}}
| {{N/A}}
| {{N/A}}
| align="right" | 0.001
| align="right" | 1
| align="right" | 4
| <small>[[Printed circuit board|PCBs]]</small> -->

==Fiber optics==
'''1000BASE-X''' is used in industry to refer to Gigabit Ethernet transmission over fiber, where options include 1000BASE-SX, 1000BASE-LX, 1000BASE-LX10, 1000BASE-BX10 or the non-standard -EX and -ZX implementations. Included are copper variants using the same [[8b/10b]] line code. 1000BASE-X is based on the physical-layer standards developed for [[Fibre Channel]].<ref>IEEE 802.3 Clause 36.1.1</ref>

{{Fibre legend}}

{| class="wikitable" style="line-height:110%;"
|-
! Name
! Standard
! Status
! style="width: 170px;" | Media
! Connector
! <small>Transceiver<br />Module</small>
! Reach<br />in m
! <small>#<br/>{{tooltip|Media|Number of physical media (wires/fibres) needed for bidirectional traffic}}<br/>(⇆)</small>
! <small>#<br/>{{tooltip|Lambdas|Number of wavelengths used in each direction}}<br/>(→)</small>
! <small>#<br/>{{tooltip|Lanes|Number of lanes (on the wire/fibre) in each direction}}<br/>(→)</small>
! Notes
|-
| colspan="11" {{success|'''Gigabit Ethernet (GbE)''' - <small>([[Data signaling rate|Data rate]]: {{nowrap|1000 Mbit/s}} - [[Line code]]: [[8B/10B]] × [[Non-return-to-zero|NRZ]] - Line rate: 1.25&nbsp;[[GBd]] - Full-Duplex {{fontcolour|grey|(''or Half-Duplex''))}}</small>}}
|-
| {{nowrap|[[Gigabit Ethernet#1000BASE-CX|1000BASE‑CX]]}}
| {{nowrap|802.3z-1998}}<br /><small>(CL39)</small>
| {{partial|legacy}}
| {{terminated|[[Twisted pair|TWP]]<br />shielded<br />[[balanced]]}}<br />(150&nbsp;Ω)
| {{terminated|<small>[[Modular connector#8P8C (8 position 8 contact)|8P8C]]<br />[[D-subminiature|DE-9]]<br/>[[Fibre Channel electrical interface#8-pin "HSSDC" cable connector (High Speed Serial Data Connection)|FC/HSSDC]]<br />{{nowrap|CX4 (SFF-8470)}}<br />{{nowrap|(IEC 61076-3-103)}}</small>}}
| {{N/A}}
| style="text-align:right;" | 25
| style="text-align:right;" | 4
| style="text-align:right;" | N/A
| style="text-align:right;" | 4
| <small>Data centers;<br />predates 1000BASE-T; rarely used.</small>
|-
| {{nowrap|[[Gigabit Ethernet#1000BASE-KX|1000BASE‑KX]]}}
| {{nowrap|802.3ap-2007}}<br /><small>(CL70)</small>
| {{active|current}}
| {{terminated|Cu-[[Backplane]]}}
| {{N/A}}
| {{N/A}}
| style="text-align:right;" | 1
| style="text-align:right;" | 1
| style="text-align:right;" | N/A
| style="text-align:right;" | 4
| <small>[[Printed circuit board|PCBs]]</small>
|-
| rowspan="3" | {{nowrap|[[Gigabit Ethernet#1000BASE‑SX|1000BASE‑SX]]}}
| rowspan="3" | {{nowrap|802.3z-1998}}<br /><small>(CL38)</small>
| rowspan="3" {{active|current}}
| rowspan="3" {{CGuest|Fibre<br /><small>'''{{fontcolour|red|770 – 860&nbsp;nm}}'''</small>}}
| rowspan="3" {{CGuest|ST<br />SC<br />LC<br />MT-RJ <ref name="MTRJ_1GbE_TCVR">{{cite web |url=http://www.te.com/commerce/DocumentDelivery/DDEController?Action=showdoc&DocId=Data+Sheet%7F1654843%7F1103%7Fpdf%7FEnglish%7FENG_DS_1654843_1103.pdf |title=Gigabit Ethernet Multimode SFP MT-RJ Transceiver |publisher=tyco Electronics |date=November 1, 2003 |access-date=August 26, 2018 }}</ref>}}
| rowspan="3" align="center" | <small>'''SFP'''<br />''<del>[[GBIC]]</del>''<br />''direct-plug''</small>
| style="background-color:orange" | {{nowrap|OM1: 275}}
| rowspan="3" align="right" | 2
| rowspan="3" align="right" | 1
| rowspan="3" align="right" | 1
| rowspan="3" | <small>Popular in intra-building LANs</small>
|-
| style="background-color:orange" | {{nowrap|OM2: 550}}
|-
| style="background-color:#7DF9FF" | {{nowrap|OM3: 1k <ref name="corning multimode 2012">{{cite web |url=https://www.corning.com/catalog/coc/documents/application-engineering-notes/AEN075.pdf |title=Multimode Optical Fiber Selection & Specification |publisher=Corning Cable Systems LLC |date=2012 |access-date=December 23, 2022 }}</ref>}}
|-
| rowspan="3" | {{nowrap|[[Gigabit Ethernet#1000BASE‑LSX|1000BASE‑LSX]]}}
| rowspan="3" {{partial|''proprietary<br /><small>(non IEEE)</small>''}}
| rowspan="3" {{active|current}}
| rowspan="3" {{CGuest|Fibre<br /><small>'''{{fontcolour|#F88379|1310&nbsp;nm}}'''</small>}}
| rowspan="3" {{CGuest|LC}}
| rowspan="3" align="center" | <small>'''SFP'''</small>
| style="background-color:orange" | {{nowrap|OM1: 2k <ref>{{cite web |url=https://www.moxa.com/getmedia/ea25d5b9-e1dd-4c78-9196-75888e1df95f/moxa-sfp-1g-series-datasheet-v1.0.pdf |title=Datasheet for SFP-1G Series |publisher=MOXA  |date=October 12, 2018 |access-date=March 21, 2020 }}</ref>}}
| rowspan="3" align="right" | 2
| rowspan="3" align="right" | 1
| rowspan="3" align="right" | 1
| rowspan="3" | <small>vendor-specific;<br />FP laser transmitter</small>
|-
| style="background-color:orange" | {{nowrap|OM2: 1k <ref>{{cite web |url=https://www.moxa.com/getmedia/ea25d5b9-e1dd-4c78-9196-75888e1df95f/moxa-sfp-1g-series-datasheet-v1.0.pdf |title=Datasheet for SFP-1G Series |publisher=MOXA  |date=October 12, 2018 |access-date=March 21, 2020 }}</ref>}}
|-
| style="background-color:#C66995" | {{nowrap|OM4: 2k <ref>{{cite web |url=https://www.fs.com/products/75795.html |title=SFP1G-SX-31 |publisher=FS.com  |date=January 1, 2019 |access-date=March 21, 2020 }}</ref>}}
|-
| rowspan="4" | {{nowrap|[[Gigabit Ethernet#1000BASE‑LX|1000BASE‑LX]]}}
| rowspan="4" | {{nowrap|802.3z-1998}}<br /><small>(CL38)</small>
| rowspan="4" {{active|current}}
| rowspan="4" {{CGuest|Fibre<br /><small>'''{{fontcolour|#F88379|1270 – 1355&nbsp;nm}}'''</small>}}
| rowspan="4" {{CGuest|SC<br />LC}}
| rowspan="4" align="center" | <small>'''SFP'''<br />{{fontcolour|grey|''GBIC''}}<br />''direct-plug''</small>
| style="background-color:orange" | {{nowrap|OM1: 550}}
| rowspan="4" align="right" | 2
| rowspan="4" align="right" | 1
| rowspan="4" align="right" | 1
| rowspan="4" |
|-
| style="background-color:orange" | {{nowrap|OM2: 550}}
|-
| style="background-color:#7DF9FF" | {{nowrap|OM3: 550}}
|-
| style="background-color:yellow" | {{nowrap|OSx: 5k}}
|-
| rowspan="4" | {{nowrap|[[Gigabit Ethernet#1000BASE‑LX10|1000BASE‑LX10]]}}
| rowspan="5" | {{nowrap|802.3ah-2004}}<br /><small>(CL59)</small>
| rowspan="4" {{active|current}}
| rowspan="4" {{CGuest|Fibre<br /><small>'''{{fontcolour|#F88379|1260 – 1360&nbsp;nm}}'''</small>}}
| rowspan="5" {{CGuest|LC}}
| rowspan="5" align="center" | <small>'''SFP'''</small>
| style="background-color:orange" | {{nowrap|OM1: 550}}
| rowspan="4" align="right" | 2
| rowspan="5" align="right" | 1
| rowspan="5" align="right" | 1
| rowspan="4" | <small>identical with -LX but with increased power/sensitivity;<br />commonly simply referred to as ''-LX'' or ''-LH'' prior to 802.3ah</small>
|-
| style="background-color:orange" | {{nowrap|OM2: 550}}
|-
| style="background-color:#7DF9FF" | {{nowrap|OM3: 550}}
|-
| style="background-color:yellow" | {{nowrap|OSx: 10k}}
|-
| {{nowrap|[[1000BASE-BX10]]}}
| {{active|current}}
| {{CGuest|Fibre<br /><small>'''{{nowrap|TX: {{fontcolour|#F88379|1260 – 1360&nbsp;nm}}<br />RX: {{fontcolour|#F49AC2|1480 – 1500&nbsp;nm}}}}'''</small>}}
| style="background-color:yellow" | {{nowrap|OSx: 10k}}
| style="text-align:right;" | 1
| <small>often simply referred to as ''-BX'' and BiDi</small>
|-
| {{nowrap|[[Gigabit Ethernet#1000BASE‑EX|1000BASE‑EX]]}}
| {{partial|''proprietary<br /><small>(non IEEE)</small>''}}
| {{active|current}}
| {{CGuest|Fibre<br /><small>'''{{fontcolour|#F88379|1310&nbsp;nm}}'''</small>}}
| {{CGuest|SC<br />LC}}
| align="center" | <small>'''SFP'''<br />{{fontcolour|grey|''GBIC''}}</small>
| style="background-color:yellow" | {{nowrap|OSx: 40k}}
| style="text-align:right;" | 2
| style="text-align:right;" | 1
| style="text-align:right;" | 1
| <small>vendor-specific</small>
|-
| {{nowrap|[[Gigabit Ethernet#1000BASE-ZX|1000BASE‑ZX / ‑EZX]]}}
| {{partial|''proprietary<br /><small>(non IEEE)</small>''}} 
| {{active|current}}
| {{CGuest|Fibre<br /><small>'''{{fontcolour|#F49AC2|1550&nbsp;nm}}'''</small>}}
| {{CGuest|SC<br />LC}}
| align="center" | <small>'''SFP'''<br />{{fontcolour|grey|''GBIC''}}</small>
| style="background-color:yellow" | {{nowrap|OSx: 70k}}
| style="text-align:right;" | 2
| style="text-align:right;" | 1
| style="text-align:right;" | 1
| <small>vendor-specific</small>
|-
| {{nowrap|[[Gigabit Ethernet#1000BASE‑RH|1000BASE‑RHx]]}}
| {{nowrap|802.3bv-2017}}<br /><small>(CL115)</small>
| {{active|current}}
| {{CGuest|Fibre<br /><small>'''{{fontcolour|orange|650&nbsp;nm}}'''</small>}}
| {{CGuest|[[Fibre optic tranceiver|FOT]]<br /><small>(PMD/MDI)</small>}}
| {{N/A}}
| style="text-align:right;" | {{nowrap|[[Plastic optical fiber|POF]]: ≤ 50}}
| style="text-align:right;" | 1
| style="text-align:right;" | 1
| style="text-align:right;" | 1
| <small>[[Automotive]], [[Industry (manufacturing)|Industry]], [[Home]]; <ref>{{cite web |url=http://www.ieee802.org/3/bv/public/Sep_2015/perezaranda_3bv_1_0915.pdf |title=1000BASE-RH PHY system simulations |publisher=IEEE 802.3bv Task Force |date=September 8, 2015 |access-date=August 25, 2018 }}</ref><ref>{{cite web |url=http://www.respice-sme.eu/fileadmin/cms/downloads/KDPOF-07_Presentation_Optical_Ethernet_Automotive.pdf |title=Optical Ethernet in Automotive |publisher=Knowledge Development for POF S.L. (KDPOF) |date=July 3, 2017 |access-date=August 25, 2018 |archive-date=September 10, 2018 |archive-url=https://web.archive.org/web/20180910014611/http://www.respice-sme.eu/fileadmin/cms/downloads/KDPOF-07_Presentation_Optical_Ethernet_Automotive.pdf |url-status=dead }}</ref><br />'''Line code: [[64b/66b encoding|64b65b]] × PAM16'''<br />'''Line rate: 325&nbsp;MBd'''<br />Variants: -RHA (50&nbsp;m), -RHB (40&nbsp;m), -RHC (15&nbsp;m).</small>
|-
| {{nowrap|1000BASE-PX}}
| {{nowrap|802.3ah-2004<br />802.3bk-2013}}<br /><small>(CL60)</small>
| {{active|current}}
| {{CGuest|Fibre<br /><small>'''{{nowrap|TX: {{fontcolour|#F88379|1270&nbsp;nm}}}}<br />{{nowrap|RX: {{fontcolour|#F49AC2|1577&nbsp;nm}}}}'''</small>}}
| {{CGuest|SC}}
| align="center" | <small>'''SFP'''<br />XFP</small>
| style="background-color:yellow" | {{nowrap|OSx:<br />10k – 40k}}
| style="text-align:right;" | 1
| style="text-align:right;" | 1
| style="text-align:right;" | 1
| <small>[[Passive Optical Network|EPON]]; [[FTTH]];<br />using point-to-multipoint topology.</small>
|-
| {{nowrap|[[Gigabit Ethernet#1000BASE‑CWDM|1000BASE‑CWDM]]}}<br /><ref name="Cisco-CWDM-SFP">{{cite web |date=December 29, 2005 |title=CWDM SFP Datasheet |url=https://www.cisco.com/c/en/us/products/collateral/interfaces-modules/cwdm-transceiver-modules/product_data_sheet09186a00801a557c.html |website=Cisco |access-date=March 22, 2020 }}</ref><ref name="FS-DWDM-info">{{cite web |title=DWDM Technology And DWDM Network Overview |url=https://community.fs.com/blog/complete-analysis-on-dwdm-technology.html |website=FS.com |access-date=March 22, 2020 |language=en |date=November 28, 2016 }}</ref>
| {{partial|''ITU-T G.694.2''}}
| {{active|current}}
| {{CGuest|Fibre<br /><small>'''{{fontcolour|#F88379|1270 – 1610&nbsp;nm}}'''</small>}}
| {{CGuest|LC}}
| align="center" | <small>'''SFP'''</small>
| style="background-color:yellow" | {{nowrap|OSx:<br />40k – 100k}}
| style="text-align:right;" | 2
| style="text-align:right;" | 1
| style="text-align:right;" | 1
| <small>[[CWDM]] makes it possible to have multiple parallel channels over 2 fibers;<br />spectral bandwidth 11&nbsp;nm;<br />capable of 18 parallel channels</small>
|- 
| {{nowrap|[[Gigabit Ethernet#1000BASE‑DWDM|1000BASE‑DWDM]]}}<br /><ref name="Cisco-DWDM-SFP">{{cite web |title=DWDM-SFP Data Sheet |url=https://www.cisco.com/c/en/us/products/collateral/interfaces-modules/dwdm-transceiver-modules/product_data_sheet0900aecd80582763.html |website=Cisco |access-date=March 22, 2020 }}</ref><ref name="FS-DWDM-info" />
| {{partial|''ITU-T G.694.1''}}
| {{active|current}}
| {{CGuest|Fibre<br /><small>'''{{fontcolour|#F88379|1528 – 1565&nbsp;nm}}'''</small>}}
| {{CGuest|LC}}
| align="center" | <small>'''SFP'''</small>
| style="background-color:yellow" | {{nowrap|OSx:<br />40k – 120k}}
| style="text-align:right;" | 2
| style="text-align:right;" | 1
| style="text-align:right;" | 1
| <small>[[DWDM]] makes it possible to have multiple parallel channels over 2 fibers;<br />spectral bandwidth 0.2&nbsp;nm;<br />capable of 45 to 160 parallel channels</small>
|-
|}

===1000BASE-SX===
1000BASE-SX is an [[optical fiber]] Gigabit Ethernet standard for operation over multi-mode fiber using a 770 to 860 [[nanometer]], [[Infrared|near infrared]] (NIR) [[light]] [[wavelength]].

The standard specifies a maximum length of 220 meters for 62.5&nbsp;μm/160&nbsp;[[Modal bandwidth|MHz×km]] [[multi-mode fiber]], 275&nbsp;m for 62.5&nbsp;μm/200&nbsp;MHz×km, 500&nbsp;m for 50&nbsp;μm/400&nbsp;MHz×km, and 550&nbsp;m for 50&nbsp;μm/500&nbsp;MHz×km multi-mode fiber.<ref>{{Cite web|url=https://kb.wisc.edu/ns/page.php?id=7829|title=Ethernet Media Standards and Distances|website=kb.wisc.edu|access-date=February 1, 2017 }}</ref><ref>IEEE 802.3 ''Table 38–2—Operating range for 1000BASE-SX over each optical fiber type''</ref> Fiber optic cable manufacturers have extended the reach of 1000BASE-SX to at least 1km when used with more modern fiber optic grades such as OM3 and OM4.<ref name="corning multimode 2012" />

This standard is highly popular for intra-building links in large office buildings, co-location facilities and carrier-neutral Internet exchanges.

Optical power specifications of SX interface: Minimum output power = −9.5&nbsp;[[dBm]]. Minimum receive sensitivity = −17&nbsp;dBm.

===1000BASE-LSX===
1000BASE-LSX is a non-standard but industry accepted<ref>{{Cite web |url=https://www.moxa.com/getmedia/ea25d5b9-e1dd-4c78-9196-75888e1df95f/moxa-sfp-1g-series-datasheet-v1.0.pdf |title=Datasheet for SFP-1G Series |publisher=MOXA |access-date=March 21, 2020 }}</ref>
term to refer to Gigabit Ethernet transmission. It is very similar to 1000BASE-SX but achieves longer distances up to 2&nbsp;km over a pair of multi-mode fibers due to higher quality optics than a SX, running on 1310&nbsp;nm wavelength lasers. It is easily confused with 1000BASE-SX or 1000BASE-LX because the use of -LX, -LX10 and -SX is ambiguous between vendors. 
The range is achieved with use of [[Fabry Perot]] laser transmitter.

===1000BASE-LX===
1000BASE-LX is an optical fiber Gigabit Ethernet standard specified in IEEE 802.3 Clause 38 which uses a long wavelength laser (1,270–1,355&nbsp;nm), and a maximum RMS spectral width of 4&nbsp;nm.

1000BASE-LX is specified to work over a distance of up to 5&nbsp;km over 10&nbsp;μm single-mode fiber.

1000BASE-LX can also run over all common types of multi-mode fiber with a maximum segment length of 550 m. For link distances greater than 300&nbsp;m, the use of a special launch conditioning patch cord may be required.<ref>{{Cite web |url=http://www.cisco.com/c/en/us/td/docs/interfaces_modules/transceiver_modules/installation/note/OL_19329.html |title=Mode-Conditioning Patch Cord Installation Note |access-date=February 14, 2009 }}</ref> This launches the laser at a precise offset from the center of the fiber which causes it to spread across the diameter of the fiber core, reducing the effect known as differential mode delay which occurs when the laser couples onto only a small number of available modes in multi-mode fiber.

===1000BASE-LX10===
1000BASE-LX10 was standardized six years after the initial gigabit fiber versions as part of the [[Ethernet in the first mile]] task group. It is practically identical to 1000BASE-LX, but achieves longer distances up to 10&nbsp;km over a pair of single-mode fiber due to higher quality optics. Before it was standardized, 1000BASE-LX10 was essentially already in widespread use by many vendors as a proprietary extension called either 1000BASE-LX/LH or 1000BASE-LH.<ref>{{Cite web |url=http://www.cisco.com/en/US/prod/collateral/modules/ps5455/ps6577/product_data_sheet0900aecd8033f885.html |title=Cisco SFP Optics For Gigabit Ethernet Applications |access-date=June 1, 2010 |publisher=Cisco Systems }}</ref>

===1000BASE-EX===
1000BASE-EX is a non-standard but industry accepted term<ref>{{cite web |title=fs SFP1G-EX-55 |url=https://www.fs.com/de-en/products/49943.html |website=FS Germany |access-date=March 30, 2020 }}</ref> to refer to Gigabit Ethernet transmission. It is very similar to 1000BASE-LX10 but achieves longer distances up to 40&nbsp;km over a pair of single-mode fibers due to higher quality optics than a LX10, running on 1310&nbsp;nm wavelength lasers. It is sometimes referred to as LH (Long Haul), and is easily confused with 1000BASE-LX10 or 1000BASE-ZX because the use of -LX(10), -LH, -EX, and -ZX is ambiguous between vendors. [[#1000BASE-ZX|1000BASE-ZX]] is a very similar non-standard longer-reach variant that uses 1550&nbsp;nm wavelength optics.

===1000BASE-BX10===
1000BASE-BX10 is capable of up to 10&nbsp;km over a single strand of [[single-mode fiber]], with a different wavelength going in each direction. The terminals on each side of the fiber are not equal, as the one transmitting downstream (from the center of the network to the outside) uses the 1490&nbsp;nm wavelength, and the one transmitting upstream uses the 1310&nbsp;nm wavelength. This is accomplished using a passive splitter prism inside each transceiver.

Other, non-standard higher-powered single-strand optics commonly known as "BiDi" (bi-directional) utilize wavelength pairs in the 1490/1550&nbsp;nm range, and are capable of reaching distances of 20, 40 and 80&nbsp;km, or greater depending on module cost, fiber path loss, splices, connectors and patch panels. Very long reach BiDi optics may use 1510/1590&nbsp;nm wavelength pairs.

===1000BASE-ZX===
1000BASE-ZX is a non-standard but multi-vendor<ref name="FS-SFP1G-ZX-55">{{cite web |title=FS SFP1G-ZX-55 |url=https://www.fs.com/de-en/products/11776.html |website=FS Germany |access-date=March 30, 2020 }}</ref> term to refer to Gigabit Ethernet transmission using 1,550&nbsp;nm wavelength to achieve distances of at least {{Convert|70|km|mi|abbr=on}} over single-mode fiber. Some vendors specify distances up to {{Convert|120|km|mi|abbr=on}} over single-mode fiber, sometimes called 1000BASE-EZX. Ranges beyond 80&nbsp;km are highly dependent upon the path loss of the fiber in use, specifically the attenuation figure in dB per km, the number and quality of connectors/patch panels and splices located between transceivers.<ref>{{cite web |title=1.25Gbps SFP Transceiver 120km |url=http://menaranet.com/download/datasheets/SFP/187-0A031-00%20SFP%201550nm%20EZX%201GbE%20-%20Product%20Datasheet-%202%20page.pdf |publisher=Menaranet |access-date=June 21, 2014 |archive-date=December 10, 2014 |archive-url=https://web.archive.org/web/20141210040945/http://menaranet.com/download/datasheets/SFP/187-0A031-00%20SFP%201550nm%20EZX%201GbE%20-%20Product%20Datasheet-%202%20page.pdf |url-status=dead }}</ref>

===1000BASE‑CWDM===
1000BASE-CWDM is a non-standard but industry accepted term<ref name="Cisco-CWDM-SFP" /><ref name="FS-DWDM-info" /> to refer to Gigabit Ethernet transmission. It is very similar to 1000BASE-LX10 but achieves longer distances up 40–120&nbsp;km, and up to 18 parallel channels over a pair of single-mode fibers due to higher quality optics than LX10 and use of CWDM, running on 1270-1610&nbsp;nm wavelength lasers.

Use of CWDM requires a Mux/Demux unit at both ends of the fiber link, a CWDM MUX/DEMUX with corresponding wavelengths, and SFP with corresponding wavelengths.<ref name="FS-DWDM-info" /> is it also possible to DWDM in serie to increase number of channels.

Most uses Wavelengths: 1270&nbsp;nm, 1290&nbsp;nm, 1310&nbsp;nm, 1330&nbsp;nm, 1350&nbsp;nm, 1370&nbsp;nm, 1390&nbsp;nm, 1410&nbsp;nm, 1430&nbsp;nm, 1450&nbsp;nm, 1470&nbsp;nm, 1490&nbsp;nm, 1510&nbsp;nm, 1530&nbsp;nm, 1550&nbsp;nm, 1570&nbsp;nm, 1590&nbsp;nm and 1610&nbsp;nm

CWDM is cheaper to use than DWDM, about 1/5-1/3 of the cost.<ref>{{cite web |title=CWDM vs. DWDM： What Are the Differences？ |url=https://medium.com/@opticalfibersolutions/cwdm-vs-dwdm-what-are-the-differences-67c1c8adeccc |website=Medium.com |access-date=March 22, 2020 |language=en |date=November 30, 2017 }}</ref><ref>{{cite web |title=CWDM - Cost-Effective Alternative to Expand Network Capacity |url=https://community.fs.com/blog/cwdm-cost-effective-alternative-to-expand-network-capacity.html |website=fs.com|access-date=March 22, 2020 |language=en |date=June 17, 2014 }}</ref> CWDM is about 5-10 times more expensive the if you have the fiber available, then traditional  -LX/-LZ transceivers.

===1000BASE‑DWDM===
1000BASE-DWDM is a non-standard but industry accepted term<ref name="Cisco-DWDM-SFP" /><ref name="FS-DWDM-info" /> to refer to Gigabit Ethernet transmission. It is very similar to 1000BASE-LX10 but achieves longer distances up 40–120&nbsp;km, and up to 64 to 160 parallel channels over a pair of single-mode fibers due to higher quality optics than LX10 and use of DWDM, running on 1528-1565&nbsp;nm wavelength lasers.

The most used channels are  CH17-61 on Wavelength 1528.77-1563-86&nbsp;nm.

To use DWDM it is necessary to use a Mux/Demux unit on both ends of the fiber link, a DWDM MUX/DEMUX with corresponding wavelengths, and SFP with corresponding wavelengths.<ref name="FS-DWDM-info" /> is it also possible to use CWDM in series to increase the number of channels.{{cn|date=January 2021}}

===1000BASE-RH''x''===
IEEE 802.3bv-2017 defines standardizes Gigabit Ethernet over step-index [[plastic optical fiber]] (POF) using -R [[64b/66b encoding|64b/65b]] large block encoding with red light (600–700&nbsp;nm). 1000BASE-RHA is intended for home and consumer use (just clamping the bare POF), 1000BASE-RHB for industrial, and 1000BASE-RHC for automotive applications.

=== Optical interoperability ===
There may be optical interoperability with respective 1000BASE-X Ethernet interfaces on the same link.<ref name="Cisco-100BASE-X">{{cite web |title=Cisco 100BASE-X SFP for Fast Ethernet SFP Ports |url=https://www02.cp-static.com/objects/pdf/2/227/1347766271_1_network-media-converters-cisco-100base-zx-for-fast-ethernet-sfp-ports-glc-fe-100zx253d.pdf |website=cisco |access-date=March 29, 2020 |archive-date=March 29, 2020 |archive-url=https://web.archive.org/web/20200329115059/https://www02.cp-static.com/objects/pdf/2/227/1347766271_1_network-media-converters-cisco-100base-zx-for-fast-ethernet-sfp-ports-glc-fe-100zx253d.pdf |url-status=dead }}</ref> It is also possible with certain types of optics to have a mismatch in wavelength.<ref>{{cite web |title=Everything You Always Wanted to Know about Optical Networking – But Were Afraid to Ask |url=https://archive.nanog.org/sites/default/files/Steenbergen.Everything_You_Need.pdf |website=archive.nanog.org |publisher=Richard A Steenbergen |access-date=March 30, 2020 }}</ref>

To achieve interoperability some criteria have to be met:<ref>{{cite web |title=Fiber incompatabilities? - Ars Technica OpenForum |url=https://arstechnica.com/civis/viewtopic.php?p=6647265&sid=1207bc662946d0bf8ff15eac6753a819#p6647265 |website=arstechnica.com |access-date=March 29, 2020 |date=June 6, 2006 }}{{sps|date=May 2020}}</ref>
* [[Line encoding]]
* [[Wavelength]]{{efn|It may be possible for certain types of optics to work with a mismatch in wavelength.<ref>{{cite web |title=Everything You Always Wanted to Know About Optical Networking – But Were Afraid to Ask |url=https://archive.nanog.org/sites/default/files/Steenbergen.Everything_You_Need.pdf |website=archive.nanog.org |publisher=Richard A Steenbergen |access-date=March 30, 2020 }}</ref>}}
* [[Duplex (telecommunications)|Duplex mode]]
* Media count
* Media type and dimension

1000BASE-X Ethernet is not backward compatible with [[100BASE-X]] and is not forward compatible with [[10 Gigabit Ethernet|10GBASE-X]].

==See also==
* [[List of interface bit rates]]
* [[Physical coding sublayer]]

==Notes==
{{Notelist}}

==References==
{{Reflist}}

==Further reading==
* [[Mark Norris (technology writer)|Norris, Mark]], ''Gigabit Ethernet Technology and Applications'', Artech House, 2002. {{ISBN|1-58053-505-4}}

==External links==
* [http://standards.ieee.org/getieee802/802.3.html Get IEEE 802.3] {{Webarchive|url=https://web.archive.org/web/20100726111446/http://standards.ieee.org/getieee802/802.3.html |date=July 26, 2010 }}
* [http://www.ieee802.org/3/ IEEE 802.3]
* [http://standards.ieee.org/announcements/802.3ab.html IEEE and Gigabit Ethernet Alliance Announce Formal Ratification of gigabit Ethernet Over Copper Standard] {{Webarchive|url=https://web.archive.org/web/20090731124319/http://standards.ieee.org/announcements/802.3ab.html |date=July 31, 2009 }} - Announcement from IEEE June 28, 1999
* [https://grouper.ieee.org/groups/802/3/ab/ IEEE P802.3ab 1000BASE-T Task Force] (historical information)
* [https://grouper.ieee.org/groups/802/3/ IEEE 802.3 CSMA/CD (ETHERNET)]
* [http://www.10gea.org/1000base-t/ 1000BASE-T Whitepaper from 10GEA] {{Webarchive|url=https://web.archive.org/web/20120702232437/http://www.10gea.org/1000base-t/ |date=July 2, 2012 }}
* [https://web.archive.org/web/20120205143649/http://www.dell.com/content/topics/global.aspx/power/en/ps1q01_hernan?c=us&l=en&cs=555 Gigabit Ethernet Auto-Negotiation]

{{Ethernet}}

[[Category:Ethernet standards]]
[[Category:Computer-related introductions in 1999]]