View source for Ethernet over twisted pair

{{Short description|Ethernet physical layers using twisted-pair cables}}
{{Use American English|date = March 2019}}
{{Twisted pair categories}}
{{multiple image|direction=vertical
| image1 = 10baseT cable.jpeg
| caption1 = Standard twisted-pair cable usable for most common types of Ethernet
| image2 = 10baseT jack.png
| caption2 = [[8P8C]] plug
}}

'''Ethernet over twisted-pair''' technologies use [[twisted-pair cable]]s for the [[physical layer]] of an [[Ethernet]] computer network. They are a subset of all [[Ethernet physical layer]]s.

Early Ethernet used various grades of [[coaxial cable]], but in 1984, [[StarLAN]] showed the potential of simple [[unshielded twisted pair]]. This led to the development of '''10BASE-T''' and its successors [[100BASE-TX]], [[1000BASE-T]], [[10GBASE-T]] and [[40GBASE-T]], supporting speeds of 10 and 100&nbsp;[[megabits per second]], then 1, 10 and 40&nbsp;gigabits per second respectively.{{efn|Generally, the higher-speed implementations support the lower-speed standards making it possible to mix different generations of equipment; with the inclusive capability designated 10/100 or 10/100/1000 for connections that support such combinations.<ref>{{cite book |title= Ethernet: the definitive guide |author= Charles E. Spurgeon |year= 2000 |publisher= OReilly Media |isbn= 978-1-56592-660-8 |url= https://books.google.com/books?id=MRChaUQr0Q0C&pg=PA123 }}</ref>{{rp|123}}}} 

Two new variants of 10-megabit-per-second Ethernet over a ''single'' twisted pair, known as '''10BASE-T1S''' and '''10BASE-T1L''', were standardized in IEEE Std 802.3cg-2019.<ref name=ieee802.3CG>{{cite web |title=PhysicalLayers Specifications and Management Parameters for 10&nbsp;Mb/s Operation and Associated Power Delivery over a Single Balanced Pair of Conductors |url=https://standards.ieee.org/standard/802_3cg-2019.html |archive-url=https://web.archive.org/web/20200318015954/https://standards.ieee.org/standard/802_3cg-2019.html |url-status=dead |archive-date=March 18, 2020 |publisher=IEEE 802.3}}</ref> 10BASE-T1S has its origins in the [[automotive industry]] and may be useful in other short-distance applications where substantial electrical noise is present.<ref>{{citation |url=https://www.analog.com/en/thought-leadership/why-10base-t1s-is-the-missing-ethernet-link.html |title=Why 10BASE-T1S Is the Missing Ethernet Link for Automotive Communications |author=Fionn Hurley |publisher=[[Analog Devices]]}}.</ref> 10BASE-T1L is a long-distance Ethernet, supporting connections up to 1&nbsp;km in length. Both of these standards are finding applications implementing the [[Internet of things]]. 10BASE-T1S is a direct competitor of [[CAN bus|CAN&nbsp;XL]] in the automotive space and includes a [[PHY-Level Collision Avoidance]] scheme (PLCA).<ref>{{cite conference | last1=Cena | first1=Gianluca | last2=Scanzio | first2=Stefano | last3=Valenzano | first3=Adriano | title=Composite CAN XL-Ethernet Networks for Next-Gen Automotive and Automation Systems | conference=2023 IEEE 19th International Conference on Factory Communication Systems (WFCS) | publisher=IEEE | date=2023-04-26 | doi=10.1109/wfcs57264.2023.10144116 | arxiv=2306.09498 }}</ref>

The earlier standards use [[8P8C modular connector]]s{{efn|The [[8P8C modular connector]] is often called ''RJ45'' after a [[Registered jack|telephone industry standard]].}} and supported cable standards range from [[Category 3 cable|Category&nbsp;3]] to [[Category&nbsp;8]]. These cables typically have four pairs of wires for each connection, although early Ethernet used only two of the pairs. Unlike the earlier -T standards, the -T1 interfaces were designed to operate over a single pair of conductors and introduce the use of two new connectors referred to as {{nobr|IEC 63171-1}}<ref name="IEC 63171-1" /> and {{nobr|IEC 63171-6}}.<ref name="IEC 63171-6" />

== History ==
The first two early designs of twisted-pair networking were [[StarLAN]], standardized by the [[IEEE Standards Association]] as {{nobr|[[IEEE 802.3]]e}} in 1986, at one megabit per second,<ref name="urs" /> and [[LattisNet]], developed in January 1987, at 10&nbsp;megabits per second.<ref name="syn" /><ref name="Wise" /> Both were developed before the 10BASE-T standard (published in 1990 as {{nobr|IEEE 802.3i}}) and used different signaling, so they were not directly compatible with it.<ref name="Network Maintenance" />

In 1988, AT&T released StarLAN&nbsp;10, named for working at {{nowrap|10 Mbit/s}}.<ref>{{cite book |title= StarLAN Technology Report, 4th Edition |year= 1991 |publisher= Architecture Technology Corporation |url= https://books.google.com/books?id=wvsgBQAAQBAJ |isbn= 9781483285054 }}</ref> The StarLAN&nbsp;10 signaling was used as the basis of 10BASE-T, with the addition of ''link beat'' to quickly indicate connection status.{{efn|By switching link beat on or off, a number of network interface cards at the time could work with either StarLAN 10 or 10BASE-T.<ref>{{cite web |last1=Ohland |first1=Louis |title=3Com 3C523 |url=http://www.walshcomptech.com/ohlandl/NIC/3com_523.html |website=Walsh Computer Technology |access-date=1 April 2015}}</ref>}}

Using twisted-pair cabling in a [[star topology]] addressed several weaknesses of the previous Ethernet standards:<!--I'm not sure this is a History section topic, but it does examine the transition to twisted pair, so I will leave it here until a better place is found, or someone makes a move to strike it which could happen since it is uncited and smells like original research.-->
* Twisted-pair cables were already in use for telephone service and were already present in many office buildings, lowering the overall cost of deployment.
* The centralized star topology was also already often in use for telephone service cabling, as opposed to the [[bus topology]] required by earlier Ethernet standards.
* Using point-to-point links was less prone to failure and greatly simplified troubleshooting compared to a shared bus.
* Exchanging cheap [[repeater hub]]s for more advanced [[switching hub]]s provided a viable upgrade path.
* Mixing different speeds in a single network became possible with the arrival of [[Fast Ethernet]].
* Depending on [[Twisted pair#Types|cable grades]], subsequent upgrading to [[Gigabit Ethernet]] or faster could be accomplished by replacing the network switches.

Although 10BASE-T is rarely used as a normal-operation signaling rate today, it is still in wide use with [[network interface controller]]s in [[wake-on-LAN]] power-down mode and for special, low-power, low-bandwidth applications. 10BASE-T is still supported on most twisted-pair Ethernet ports with up to [[Gigabit Ethernet]] speed.

== Naming ==
{{see also|Ethernet physical layer#Naming conventions}}

The common names for the standards derive from aspects of the physical media. The leading number (''10'' in 10BASE-T) refers to the transmission speed in Mbit/s. ''BASE'' denotes that [[baseband]] transmission is used. The ''T'' designates twisted-pair cable. Where there are several standards for the same [[transmission speed]], they are distinguished by a letter or digit following the T, such as ''TX'' or ''T4'', referring to the encoding method and number of lanes.<ref>IEEE 802.3 ''1.2.3 Physical Layer and media notation''</ref>

== Cabling ==
[[File:Rj45plug-8p8c.png|thumb|240px|[[8P8C]] modular plug pin positioning]]

{| class="wikitable" style="float:right;clear:right;margin-left:1em"
|+ [[ANSI/TIA-568]] T568A termination <!--standard name is 'B' termination options are 'A' or 'B'-->
! Pin !! Pair !! Wire{{efn|name=tipring|The terms used in the explanations of the 568 standards, [[tip and ring]], refer to [[Phone connector (audio)|older communication technologies]], and equate to the [[Electric charge|positive and negative]] parts of the connections.}} !! Color
|-
| 1 || 3 || tip
| [[File:Wire white green stripe.svg|60px|Pair 3 Wire 1]] white/green
|-
| 2 || 3 || ring
| [[File:Wire green.svg|60px|Pair 3 Wire 2]] green
|-
| 3 || 2 || tip
| [[File:Wire white orange stripe.svg|60px|Pair 2 Wire 1]] white/orange
|-
| 4 || 1 || ring
| [[File:Wire blue.svg|60px|Pair 1 Wire 2]] blue
|-
| 5 || 1 || tip
| [[File:Wire white blue stripe.svg|60px|Pair 1 Wire 1]] white/blue
|-
| 6 || 2 || ring
| [[File:Wire orange.svg|60px|Pair 2 Wire 2]] orange
|-
| 7 || 4 || tip
| [[File:Wire white brown stripe.svg|60px|Pair 4 Wire 1]] white/brown
|-
| 8 || 4 || ring
| [[File:Wire brown.svg|60px|Pair 4 Wire 2]] brown
|}
{| class="wikitable" style="float:right;clear:right;margin-left:1em"
|+ [[ANSI/TIA-568]] T568B termination <!--standard name is 'B' termination options are 'A' or 'B'-->
! Pin !! Pair !! Wire{{efn|name=tipring}} !! Color
|-
| 1 || 2 || tip
| [[File:Wire white orange stripe.svg|60px|Pair 2 Wire 1]] white/orange
|-
| 2 || 2 || ring
| [[File:Wire orange.svg|60px|Pair 2 Wire 2]] orange
|-
| 3 || 3 || tip
| [[File:Wire white green stripe.svg|60px|Pair 3 Wire 1]] white/green
|-
| 4 || 1 || ring
| [[File:Wire blue.svg|60px|Pair 1 Wire 2]] blue
|-
| 5 || 1 || tip
| [[File:Wire white blue stripe.svg|60px|Pair 1 Wire 1]] white/blue
|-
| 6 || 3 || ring
| [[File:Wire green.svg|60px|Pair 3 Wire 2]] green
|-
| 7 || 4 || tip
| [[File:Wire white brown stripe.svg|60px|Pair 4 Wire 1]] white/brown
|-
| 8 || 4 || ring
| [[File:Wire brown.svg|60px|Pair 4 Wire 2]] brown
|}

Most Ethernet cables are wired ''straight-through'' (pin 1 to pin 1, pin 2 to pin 2, and so on). In some instances, the ''[[Ethernet crossover cable|crossover]]'' form (receive to transmit and transmit to receive) may still be required.

A cable for Ethernet may be wired to either the [[ANSI/TIA-568#T568A and T568B termination|T568A or T568B]] termination standard at both ends of the cable. Since these standards differ only in that they swap the positions of pairs 2 and 3{{dash}}the only pairs used by the formerly common 10BASE-T and 100BASE-TX{{dash}}a cable with T568A wiring at one end and T568B at the other functions as a crossover cable for the older, two-pair standards.

A 10BASE-T or 100BASE-TX host normally uses connector wiring called ''[[medium dependent interface]]'' (''MDI''), transmitting on pins 1 and 2 and receiving on pins 3 and 6. An infrastructure node (such as a [[Ethernet hub|hub]] or a [[Ethernet switch|switch]]) normally uses the complementary wiring arrangement, called ''MDI-X'', the ''X'' standing for ''-crossover''. MDI-X simply reverses the pairs, transmitting on pins 3 and 6 and receiving on pins 1 and 2. These ports are connected using a [[straight-through cable]] so each transmitter talks to the receiver on the other end of the cable. (Modern twisted-pair Ethernet uses all four pairs, differently, and the MDI–MDI-X distinction does not apply.)

Later equipment often can automatically switch between MDI and MDI-X arrangements as needed, obviating crossover cables and manual selection, but in the conventional arrangement, when two nodes having the same (fixed) type of port need to be connected, a crossover cable is required. If both devices being connected support 1000BASE-T, they will connect regardless of whether a straight-through or crossover cable is used.<ref>IEEE 802.3 ''40.1.4 Signaling''</ref>

A 10BASE-T transmitter sends two [[differential signaling|differential]] voltages, +2.5&nbsp;V or −2.5&nbsp;V. A 100BASE-TX transmitter sends three differential voltages, +1&nbsp;V, 0&nbsp;V, or −1&nbsp;V.<ref>
{{cite book
|title = Electromagnetic Compatibility: principles and applications
|url = https://books.google.com/books?id=392CdZHdUDEC&pg=PA240
|author = David A. Weston |publisher= CRC Press |year= 2001
|isbn = 0-8247-8889-3 |pages= 240–242
|access-date = June 11, 2011
}}
</ref> Unlike earlier Ethernet standards using [[broadband]] and [[coaxial cable]], such as [[10BASE5]] (thicknet) and [[10BASE2]] (thinnet), 10BASE-T does not specify the exact type of wiring to be used but instead specifies certain characteristics that a cable must meet. This was done in anticipation of using 10BASE-T in existing twisted-pair wiring systems that did not conform to any specified wiring standard. Some of the specified characteristics are [[attenuation]], [[characteristic impedance]], [[propagation delay]], and several types of [[crosstalk]]. Cable testers are widely available to check these parameters to determine if a cable can be used with 10BASE-T. These characteristics are expected to be met by 100 meters of 24-[[American wire gauge|gauge]] unshielded twisted-pair cable. However, with high-quality cabling, reliable cable runs of 150 meters or longer are often achievable and are considered viable by technicians familiar with the 10BASE-T specification.{{Citation needed|date=February 2011}}

100BASE-TX follows the same wiring patterns as 10BASE-T, but is more sensitive to wire quality and length, due to the higher [[bit rate]]s.

1000BASE-T uses all four pairs bi-directionally using [[Telephone hybrid|hybrid circuits]] and [[Echo suppression and cancellation|cancellers]].<ref>IEEE 802.3 ''40.1.3 Operation of 1000BASE-T''</ref> Data is encoded using 4D-PAM5; four dimensions using [[pulse-amplitude modulation]] (PAM) with five [[voltage]]s, −2&nbsp;V, −1&nbsp;V, 0&nbsp;V, +1&nbsp;V, and +2&nbsp;V.<ref>{{cite web |url=https://grouper.ieee.org/groups/802/3/minutes/july98/E2_0798.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://grouper.ieee.org/groups/802/3/minutes/july98/E2_0798.pdf |archive-date=2022-10-09 |url-status=live |author=Steve Prior |title=1000BASE-T Duffer's Guide to Basics and Startup |access-date=2011-02-18}}</ref> While +2&nbsp;V to −2&nbsp;V may appear at the pins of the line driver, the voltage on the cable is nominally +1&nbsp;V, +0.5&nbsp;V, 0&nbsp;V, −0.5&nbsp;V and −1&nbsp;V.<ref>{{cite web |url=https://www.eetimes.com/voltage-mode-line-drivers-save-on-power/ |author1=Nick van Bavel |author2=Phil Callahan |author3=John Chiang |title=Voltage-mode line drivers save on power |website=[[EE Times]] |date=2004-10-25 |access-date=2022-08-30}}</ref>

100BASE-TX and 1000BASE-T were both designed to require a minimum of [[Category 5 cable]] and also specify a maximum cable length of {{Convert|100|m||abbr=}}.

=== Shared cable ===
{{See also|Category 5 cable#Shared cable}}

10BASE-T and 100BASE-TX require only two pairs (pins 1–2, 3–6) to operate. Since common Category 5 cable has four pairs, it is possible to use the spare pairs (pins 4–5, 7–8) in 10- and 100-Mbit/s configurations for other purposes. The spare pairs may be used for [[power over Ethernet]] (PoE), for two [[plain old telephone service]] (POTS) lines, or for a second 10BASE-T or 100BASE-TX connection. In practice, great care must be taken to separate these pairs as 10/100-Mbit/s Ethernet equipment [[Electrical termination|electrically terminates]] the unused pins ("Bob Smith Termination").<ref>{{cite web|url=https://resources.altium.com/p/bob-smith-termination-it-correct-ethernet |title=Bob Smith Termination: Is it Correct for Ethernet? |last=Peterson |first=Zachariah |date=2020-10-28 |website=altium.com |access-date=2022-05-14}}</ref> Shared cable is not an option for Gigabit Ethernet as 1000BASE-T requires all four pairs to operate.

=== Single-pair{{anchor|SPE|Single-pair Ethernet}} ===
<!-- {{main|Single Pair Ethernet}} -- redirect back to this section -->
In addition to the more computer-oriented two and four-pair variants, the [[Classic Ethernet#10BASE-T1|10BASE-T1]],<ref>IEEE 802.3cg-2019 Clause 146–147.</ref> [[100BASE-T1]]<ref>IEEE 802.3bw-2015 Clause 96.</ref> and [[1000BASE-T1]]<ref>{{Cite web |url=http://www.ieee802.org/3/bp/ |title=IEEE P802.3bp 1000BASE-T1 PHY Task Force |publisher=IEEE 802.3 |date=2016-07-29 }}</ref> '''single-pair Ethernet''' ('''SPE''') physical layers are intended for [[Automotive]], [[IoT]], and [[Machine to machine|M2M]] applications<ref>{{cite web| url = https://planetechusa.com/blog/ieee-standardizes-802-3bw-ethernet-adopts-automobile-application/| title = New 802.3bw Ethernet Auto Standard Leaves LVDS Cables in the Dust| date = 8 April 2016}}</ref> or as optional data channels in other interconnect applications.<ref>IEEE 802.3bw Clause 96 and 802.3bp Clause 97.</ref> The distances that single pair operates at full duplex depends on the speed: 1000&nbsp;m (1&nbsp;km) with 802.3cg-2019 10BASE-T1L; {{cvt|15|m}} with 100BASE-T1 (link segment type&nbsp;A); up to {{cvt|40|m}} using 1000BASE-T1 link segment type&nbsp;B with up to four in-line connectors. Both physical layers require a balanced twisted pair with an [[Impedance (electrical)|impedance]] of 100&nbsp;Ω. The cable must be capable of transmitting 600&nbsp;MHz for 1000BASE-T1 and 66&nbsp;MHz for 100BASE-T1. 2.5&nbsp;Gbit/s, 5&nbsp;Gbit/s, and 10&nbsp;Gbit/s over a 15&nbsp;m single pair is standardized in 802.3ch-2020.<ref>{{cite web | title = IEEE Std 802.3ch-2020: Multi-Gig Automotive Ethernet PHY | url = https://blog.siemon.com/standards/ieee-p802-3ch-multi-gig-automotive-ethernet-phy | first = Valerie | last = Maguire | date = 2020-06-04 }}</ref> In June 2023, 802.3cy added 25&nbsp;Gbit/s speeds at lengths up to 11&nbsp;m.<ref name="ieee802.3cy-2023">{{cite web | url = https://standards.ieee.org/ieee/802.3cy/10280/ | archive-url = https://web.archive.org/web/20220516162342/https://standards.ieee.org/ieee/802.3cy/10280/ | url-status = dead | archive-date = May 16, 2022 | title = Physical Layer Specifications and Management Parameters for 25 Gb/s - Electrical Automotive Ethernet | publisher = IEEE | date = 2023-08-11 }}</ref>

Similar to PoE, [[Power over Data Lines]] (PoDL) can provide up to 50&nbsp;W to a device.<ref>IEEE 802.3bu-2016 ''104. Power over Data Lines (PoDL) of Single Balanced Twisted-Pair Ethernet''.</ref>
{| class="wikitable"
|+ Single-pair Ethernet (SPE)
|-
! Wire colour
! PMA Signal
|-
| [[File:Wire blue.svg|60px|Blue]]
| BI_DA+
|-
| [[File:Wire white.svg|60px|White]]
| BI_DA−
|}

== Connectors ==
[[File:M12X vs 8P8C ethernet connectors.webp|thumb|[[Category 6A cable|Cat 6A cable]] with an M12X connector in one end and a modular connector in the other]]

* [[8P8C modular connector]]: For stationary uses in controlled environments, from homes to [[datacenter]]s, this is the dominant connector. Its fragile locking tab otherwise limits its suitability and durability. Bandwidths supporting up to [[Cat 8]] cabling are defined for this connector format.
* M12X: This is the [[M12 connector]] designated for Ethernet, standardized as IEC 61076-2-109. It is a 12&nbsp;mm metal screw that houses 4 shielded pairs of pins. Nominal bandwidth is 500&nbsp;MHz (Cat 6A). The connector family is used in chemically and mechanically harsh environments such as factory automation and transportation. Its size is similar to the modular connector.
* [[#Single-pair|Single-pair Ethernet]] defines its own connectors:
** IEC 63171-1 ''LC'':<ref name="IEC 63171-1"/> This is a 2-pin connector with a similar locking tab to the modular connector, if thicker.
** IEC 63171-6 ''industrial'':<ref name="IEC 63171-6"/> This standard defines five 2-pin connectors that differ in their locking mechanisms, and one 4-pin connector with dedicated pins for power. The locking mechanisms range from a metal locking tab to [[IEC metric screw sized connectors|M8 and M12 connectors]] with screw or push-pull locking. The 4-pin connector is only defined with M8 screw locking.

== Autonegotiation and duplex ==
{{Main|Autonegotiation}}
Ethernet over twisted-pair standards up through Gigabit Ethernet define both [[full-duplex]] and [[half-duplex]] communication. However, half-duplex operation for gigabit speed is not supported by any existing hardware.<ref>{{Cite book|title=Gigabit Ethernet: Technology and Applications for High-Speed LANs |chapter=10 |last=Seifert |first=Rich |publisher=Addison Wesley |year=1998 |isbn=0-201-18553-9}}</ref><ref>{{Cite web|url=http://www.cisco.com/c/en/us/support/docs/lan-switching/ethernet/10561-3.html#gb |title=Configuring and Troubleshooting Ethernet 10/100/1000Mb Half/Full Duplex Auto-Negotiation |publisher=Cisco |date=2009-10-28 |access-date=2015-02-15}}</ref> Higher speed standards, [[2.5GBASE-T]] up to [[40GBASE-T]]<ref name=bq>{{cite web|title=IEEE P802.3bq 40GBASE-T Task Force|url=http://www.ieee802.org/3/bq/|publisher=IEEE 802.3}}</ref> running at 2.5 to {{nowrap|40 Gbit/s}}, consequently define only full-duplex point-to-point links which are generally connected by [[network switch]]es, and do not support the traditional shared-medium [[CSMA/CD]] operation.<ref name="Palmer">{{cite book|author=Michael Palmer|title=Hands-On Networking Fundamentals, 2nd ed|url=https://books.google.com/books?id=-QELAAAAQBAJ&pg=PA180|publisher=Cengage Learning|isbn=978-1-285-40275-8|page=180|date=2012-06-21}}</ref>

Many different modes of operations (10BASE-T half-duplex, 10BASE-T full-duplex, 100BASE-TX half-duplex, etc.) exist for Ethernet over [[twisted pair]], and most [[network adapter]]s are capable of different modes of operation. [[Autonegotiation]] is required in order to make a working 1000BASE-T connection.

When two linked interfaces are set to different [[Duplex (telecommunications)|duplex]] modes, the effect of this [[duplex mismatch]] is a network that functions much more slowly than its nominal speed. Duplex mismatch may be inadvertently caused when an administrator configures an interface to a fixed mode (e.g. {{nowrap|100 Mbit/s}} full-duplex) and fails to configure the remote interface, leaving it set to autonegotiate. Then, when the auto-negotiation process fails, half-duplex is assumed by the autonegotiating side of the link.

== Variants ==
[[File:twisted pair based ethernet.svg|600px|Comparison of twisted-pair-based Ethernet technologies]]
{{mw-datatable}}
{| class="wikitable sortable plainrowheaders mw-datatable" style="line-height:110%; text-align: right;" 
|+ Comparison of twisted-pair-based Ethernet physical transport layers (TP-PHYs)<ref name="TDG_ETH_2nd">{{cite book |title=Ethernet: The Definitive Guide |edition=2nd |author=Charles E. Spurgeon |publisher=O'Reilly Media |year=2014 |isbn=978-1-4493-6184-6}}</ref>
|-
! scope="col" | Name
! scope="col" | Standard (IEEE 802.3 clause number)
! scope="col" | Status
! scope="col" | Speed {{nowrap|(Mbit/s)}}{{Efn-ua|name=speed}}
! scope="col" | Pairs required
! scope="col" | Lanes per direction
! scope="col" | Data rate efficiency {{nowrap|(bit/s/Hz)}}{{Efn-ua|name=bitsperhertz}}
! scope="col" | [[Line code]]
! scope="col" | [[Symbol rate]] per lane (MBd) 
! scope="col" | Bandwidth (MHz){{Efn-ua|name=frequency}}
! scope="col" | Max distance (m)
! scope="col" | Cable{{Efn-ua|name=catreach}}
! scope="col" | Cable rating (MHz)
! scope="col" | Intended usage
|-
! scope="row" | [[StarLAN]]-1 ''1BASE5''
| style="text-align:left;" | {{nowrap|802.3e-1987}}
| {{N/A|obsolete}}
| 1
| 2
| 1
| 1
| [[Manchester code|PE]]
| 1
| 1
| 250
| style="text-align:center;" | [[Category 2 cable|Cat&nbsp;2]]
| data-sort-value="12" | ~12
| style="text-align:center;" | [[LAN]]
|-
! scope="row" | [[StarLAN]]-10
| style="text-align:left;" | {{nowrap|802.3e-1988}}
| {{N/A|obsolete}}
| 10
| 2
| 1
| 1
| PE
| 10
| 10
| data-sort-value="100" | ~100
| style="text-align:center;" | [[Category 3 cable|Cat&nbsp;3]]
| data-sort-value="12" | ~12
| style="text-align:center;" | LAN
|-
! scope="row" | [[LattisNet]]
| style="text-align:left;" | {{fontcolour|grey|''pre 802.3i-1990''}}
| {{N/A|obsolete}}
| 10
| 2
| 1
| 1
| PE
| 10
| 10
| 100
| style="text-align:center;" | [[Category 3 cable|Cat&nbsp;3]]
| data-sort-value="12" | ~12
| style="text-align:center;" | LAN
|- style="background-color: #FFD863"
! scope="row" | {{nowrap|[[Classic Ethernet|10BASE-T]]}}
| style="text-align:left;" | {{nowrap|802.3i-1990}} (CL14)
| {{partial|legacy}}
| 10
| 2
| 1
| 1
| PE
| 10
| 10
| 100
| style="text-align:center;" | [[Category 3 cable|Cat&nbsp;3]]
| 16
| style="text-align:center;" | LAN <ref>{{cite web |url=https://www.ccontrols.com/pdf/ExtV2N6.pdf |archive-url=https://ghostarchive.org/archive/20221009/https://www.ccontrols.com/pdf/ExtV2N6.pdf |archive-date=2022-10-09 |url-status=live |title=Introduction To Fast Ethernet |publisher=Contemporary Control Systems, Inc. |date=2001-11-01 |accessdate=2018-08-25}}</ref>
|-
! scope="row" | {{nowrap|10BASE-T1S}}
| style="text-align:left;" | {{nowrap|{{fontcolour|blue|802.3cg-2019}}}} (CL147)
| {{active|current}}
| 10
| 1
| 1
| 0.8
| [[4B5B]] [[Differential Manchester encoding|DME]]
| 25 
| 12.5
| data-sort-value="15" | 15 or 25{{Efn-ua|name=t1s}}
| style="text-align:center;" | [[Single Pair Ethernet|SPE]]
| 25
| style="text-align:center;" | [[Automotive]], [[IoT]], [[Machine to machine|M2M]] 
|-
! scope="row" | {{nowrap|10BASE-T1L}}
| style="text-align:left;" | {{nowrap|{{fontcolour|blue|802.3cg-2019}}}} (CL146)
| {{active|current}}
| 10
| 1
| 1
| 2.6{{overline|6}}
| [[4B3T]] [[PAM-3]]
| 7.5 
| 3.75
| 1,000
| style="text-align:center;" | [[Single Pair Ethernet|SPE]]
| 20
| style="text-align:center;" | Automotive, IoT, M2M
|-
! scope="row" | {{nowrap|[[100BASE-T1]]}}
| style="text-align:left;" | {{nowrap|802.3bw-2015}} (CL96)
| {{active|current}}
| 100
| 1
| 1
| 3
| [[3B2T]] PAM-3
| 66.6{{overline|6}}
| 33.3{{overline|3}}
| 15
| style="text-align:center;" | [[Single Pair Ethernet|SPE]]
| 100
| style="text-align:center;" | Automotive, IoT, M2M
|-
! scope="row" | {{nowrap|[[100BaseVG]]}}
| style="text-align:left;" | {{nowrap|802.12-1995}}
| {{N/A|obsolete}}
| 100
| 4
| 4
| 1.6{{overline|6}}
| [[5B6B]] ''Half-duplex only''
| 30
| 15
| 100
| style="text-align:center;" | [[Category 3 cable|Cat&nbsp;3]]
| 16
| {{N/A|''Market failure''}}
|-
! scope="row" | {{nowrap|[[100BASE-T4]]}}
| style="text-align:left;" | {{nowrap|802.3u-1995}} (CL23)
| {{N/A|obsolete}}
| 100
| 4
| 3
| 2.6{{overline|6}}
| [[8B6T]] PAM-3 ''Half-duplex only''
| 25
| 12.5
| 100
| style="text-align:center;" | [[Category 3 cable|Cat&nbsp;3]]
| 16
| {{N/A|''Market failure''}}
|-
! scope="row" | {{nowrap|[[100BASE-T2]]}}
| style="text-align:left;" | {{nowrap|802.3y-1997}} (CL32)
| {{N/A|obsolete}}
| 100
| 2
| 2
| 4
| [[LFSR]] PAM-5
| 25
| 12.5
| 100
| style="text-align:center;" | [[Category 3 cable|Cat&nbsp;3]]
| 16
| {{N/A|''Market failure''}}
|- style="background-color: #FEFE66"
! scope="row" | {{nowrap|[[100BASE-TX]]}}
| style="text-align:left;" | {{nowrap|802.3u-1995}} (CL25)
| {{active|current}}
| 100
| 2
| 1
| 3.2
| 4B5B [[MLT-3]] [[Non-return-to-zero#Non-return-to-zero_inverted|NRZ-I]]
| 125
| 31.25
| 100
| style="text-align:center;" | [[Category 5 cable|Cat&nbsp;5]]
| 100
| style="text-align:center;" | LAN
|- 
! scope="row" | {{nowrap|[[Gigabit Ethernet#1000BASE-TX|1000BASE‑TX]]}}
| style="text-align:left;" | {{nowrap|802.3ab-1999}} (CL25),<br />{{nowrap|TIA/EIA 854 (2001)}}
| {{N/A|obsolete}}
| 1,000
| 4
| 2
| 4
| PAM-5
| 250
| 125
| 100
| style="text-align:center;" | [[Category 6 cable|Cat&nbsp;6]]
| 250
| {{N/A|''Market failure''}}
|- style="background-color: #dcef60"
! scope="row" | {{nowrap|[[1000BASE‑T]]}}
| style="text-align:left;" | {{nowrap|802.3ab-1999}} (CL40)
| {{active|current}}
| 1,000
| 4
| 4
| 4
| [[Trellis coded modulation|TCM]] 4D-PAM-5
| 125
| 62.5
| 100
| style="text-align:center;" | [[Category 5 cable|Cat&nbsp;5]]
| 100
| style="text-align:center;" | LAN
|-
! scope="row" | {{nowrap|[[1000BASE-T1]]}}
| style="text-align:left;" | {{nowrap|802.3bp-2016}} (CL97)
| {{active|current}}
| 1,000
| 1
| 1
| 2.6{{overline|6}}
| PAM-3 80B/81B RS-FEC
| 750
| 375
| 40
| style="text-align:center;" | [[Single Pair Ethernet|SPE]]
| 500
| style="text-align:center;" | Automotive, IoT, M2M
|- style="background-color: #A0DB76"
! scope="row" | {{nowrap|[[2.5GBASE-T]]}}
| style="text-align:left;" | {{nowrap|802.3bz-2016}} (CL126)
| {{active|current}}
| 2,500
| 4
| 4
| 6.25
| 64B65B PAM-16 [[128-DSQ]]
| 200
| 100
| 100
| style="text-align:center;" | [[Category 5e cable|Cat&nbsp;5e]]
| 100
| style="text-align:center;" | LAN
|-
! scope="row" | {{nowrap|2.5GBASE-T1}}
| style="text-align:left;" | {{nowrap|{{fontcolour|blue|802.3ch-2020}}}} (CL149)
| {{active|current}}
| 2,500
| 1
| 1
| 3.5{{overline|5}}
| 64B/65B PAM-4 RS-FEC
| 1,406.25
| 703.125
| 15
| style="text-align:center;" | [[Single Pair Ethernet|SPE]]
| 1,000
| style="text-align:center;" | Automotive, IoT, M2M
|- style="background-color: #84DBBF"
! scope="row" | {{nowrap|[[5GBASE-T]]}}
| style="text-align:left;" | {{nowrap|802.3bz-2016}} (CL126)
| {{active|current}}
| 5,000
| 4
| 4
| 6.25
| 64B65B PAM-16 128-DSQ
| 400
| 200
| 100
| style="text-align:center;" | [[Category 6 cable|Cat&nbsp;6]]
| 250
| style="text-align:center;" | LAN
|-
! scope="row" | {{nowrap|5GBASE-T1}}
| style="text-align:left;" | {{nowrap|{{fontcolour|blue|802.3ch-2020}}}} (CL149)
| {{active|current}}
| 5,000
| 1
| 1
| 3.5{{overline|5}}
| 64B/65B PAM-4 RS-FEC
| 2,812.5
| 1,406.25
| 15
| style="text-align:center;" | [[Single Pair Ethernet|SPE]]
| 2,000
| style="text-align:center;" | Automotive, IoT, M2M
|- style="background-color: #79D2F8"
! scope="row" | {{nowrap|[[10GBASE-T]]}}
| style="text-align:left;" | {{nowrap|802.3an-2006}} (CL55)
| {{active|current}}
| 10,000
| 4
| 4
| 6.25
| 64B65B PAM-16 128-DSQ
| 800
| 400
| 100
| style="text-align:center;" | [[Category 6A cable|Cat&nbsp;6A]]
| 500
| style="text-align:center;" | LAN, [[Data Center]]
|-
! scope="row" | {{nowrap|10GBASE-T1}}
| style="text-align:left;" | {{nowrap|{{fontcolour|blue|802.3ch-2020}}}} (CL149)
| {{active|current}}
| 10,000
| 1
| 1
| 3.5{{overline|5}}
| 64B/65B PAM-4 RS-FEC
| 5,625
| 2,812.5
| 15
| style="text-align:center;" | [[Single Pair Ethernet|SPE]]
| 4,000
| style="text-align:center;" | Automotive, IoT, M2M
|-
! scope="row" | {{nowrap|[[25GBASE-T]]}}
| style="text-align:left;" | {{nowrap|802.3bq-2016}} (CL113)
|rowspan=2 {{active|current (not marketed)}}
| 25,000
| 4
| 4
| 6.25
| PAM-16 RS-FEC (192, 186) LDPC
| 2,000
| 1,000
| 30
| style="text-align:center;" | [[Category 8 cable|Cat&nbsp;8]]
| 2,000
| style="text-align:center;" | LAN, Data Center
|-
! scope="row" | {{nowrap|[[40GBASE-T]]}}
| style="text-align:left;" | {{nowrap|802.3bq-2016}} (CL113)
| 40,000
| 4
| 4
| 6.25
| PAM-16 RS-FEC (192, 186) LDPC
| 3,200
| 1,600
| 30
| style="text-align:center;" | [[Category 8 cable|Cat&nbsp;8]]
| 2,000
| style="text-align:center;" | LAN, Data Center
|-
! scope="col" | Name
! scope="col" | Standard
! scope="col" | Status
! scope="col" | Speed {{nowrap|(Mbit/s)}}{{Efn-ua|name=speed}}
! scope="col" | Pairs required
! scope="col" | Lanes per direction
! scope="col" | Data rate efficiency {{nowrap|(bit/s/Hz)}}{{Efn-ua|name=bitsperhertz}}
! scope="col" | [[Line code]]
! scope="col" | [[Symbol rate]] per lane (MBd) 
! scope="col" | Bandwidth (MHz){{Efn-ua|name=frequency}}
! scope="col" | Max distance (m)
! scope="col" | Cable{{Efn-ua|name=catreach}}
! scope="col" | Cable rating (MHz)
! scope="col" | Usage
|}

{{notelist-ua|refs=
{{efn-ua|name=speed|Transfer speed{{nbsp}}{{=}} lanes{{nbsp}}× bits per hertz{{nbsp}}× spectral bandwidth}}
{{efn-ua|name=bitsperhertz|Effective bit/s per hertz per lane after loss to encoding overhead}}
{{efn-ua|name=frequency|The [[spectral bandwidth]] is the maximum rate at which the signal will complete one cycle. It is typically half the [[symbol rate]], because one can send a symbol both at the positive and negative peak of the cycle. Exceptions are 10BASE-T where it is equal because it uses [[Manchester code]], and 100BASE-TX where it is one quarter because it uses [[MLT-3 encoding]].}}
{{efn-ua|name=catreach|At shorter cable length, it is possible to use cables of a lower grade than required for 100{{nbsp}}m. For example, it is possible to use 10GBASE-T on a {{no wrap|[[Cat 6]]}} cable of 55{{nbsp}}m or less. Likewise 5GBASE-T is expected to work with Cat{{nbsp}}5e in most use cases.}}
{{efn-ua|name=t1s|15&nbsp;m for point-to-point links, 25&nbsp;m for mixing/multi-tap segments}}
}}

== See also ==
* [[Classic Ethernet]]
* [[25-pair color code]]
* [[Copper cable certification]]
* [[Ethernet extender]]
* [[Network isolator]]
* [[PHY-Level Collision Avoidance]], used in 10BASE-T1
* [[Structured cabling]]

== Notes ==
{{notelist}}

== References ==
<references>

<ref name="urs">{{cite book
|title= The triumph of Ethernet: technological communities and the battle for the LAN standard
|author= Urs von Burg |publisher= Stanford University Press
|year= 2001
|pages= 175–176, 255–256
|url= https://books.google.com/books?id=ooBqdIXIqbwC&pg=PA175
|isbn= 978-0-8047-4095-1
}}</ref>
<ref name="syn">{{cite news
| author =Paula Musich
| title = User lauds SynOptic system: LattisNet a success on PDS
| url = https://books.google.com/books?id=hBwEAAAAMBAJ&pg=PA2
| newspaper = Network World
| date = August 3, 1987
| volume=4 |number= 31
| pages = 2, 39 |access-date= June 10, 2011
}}</ref>
<ref name="Wise">{{cite news
| author = W.C. Wise, Ph.D.
| title = Yesterday, somebody asked me what I think about LattisNet. Here's what I told him in a nutshell
| url = https://books.google.com/books?id=4QQAAAAAMBAJ&pg=PA13
| work= CIO Magazine |volume=2 |number=6
| date = March 1989 |page=13
| access-date = June 11, 2011
}} (Advertisement)</ref>
<ref name="Network Maintenance">{{cite book
| title = Network Maintenance and Troubleshooting Guide
| publisher= Fluke Networks
| url = https://books.google.com/books?id=AtBeNTDGfhEC&q=starLAN+vs+LattisNet&pg=SL2-PA4
| isbn = 1-58713-800-X
| year = 2002
| page = B-4
}}</ref>
<ref name="IEC 63171-1">{{cite book
| title = IEC 63171-1 (draft 48B/2783/FDIS, 17 Jan. 2020), Connectors for electrical and electronic equipment—Part 1: Detail specification for 2-way, shielded or unshielded, free and fixed connectors: mechanical mating information, pin assignment and additional requirements for TYPE 1 / Copper LC style.
| publisher= International Electrotechnical Commission
| year = 2020
}}</ref>
<ref name="IEC 63171-6">{{cite book
| title = IEC 63171-6:2020, Connectors for electrical and electronic equipment—Part 6: Detail specification for 2-way and 4-way (data/power), shielded, free and fixed connectors for power and data transmission with frequencies up to 600&nbsp;MHz. 
| publisher= International Electrotechnical Commission
| year = 2020
}}</ref>

</references>

== External links ==
*{{WikiHow|Make-a-Network-Cable|Make a Network Cable}}
*[http://www.ertyu.org/steven_nikkel/ethernetcables.html How to create your own Ethernet Cables]

{{Ethernet}}

{{DEFAULTSORT:Ethernet Over twisted pair}}
[[Category:Ethernet cables]]
[[Category:Physical layer protocols]]
[[Category:Local loop]]