10BASE-T is an implementation of Ethernet which allows stations to be attached via twisted pair cable. The name 10BASE-T is derived from several aspects of the physical medium. The 10 refers to the transmission speed of 10 Mbit/s. The BASE is short for baseband. This means only one Ethernet signal is present on the send and/or receive pair. In other words there is no multiplexing as with broadband transmissions. The T comes from twisted pair, which is the type of cable that is used.

10BASE-T uses RJ-45 jacks wired to either the TIA-568A or TIA-568B standard. Only the second and third pairs are used (orange and green). If the wiring standard is identical on both ends the segment is a patch cable suitable for transmission between a hub/switch/patch panel and a node. If the wiring standards are opposite on either end the segment is a crossover cable suitable for connecting a node to a node or a hub/switch to another hub/switch. The EIA/TIA 568 standards are as follows:

RJ-45 Wiring (EIA/TIA-568A)

Pin	Pair	Wire	Color
1	3	1	white/green
2	3	2	green/white
3	2	1	white/orange
4	1	2	blue/white
5	1	1	white/blue
6	2	2	orange/white
7	4	1	white/brown
8	4	2	brown/white

RJ-45 Wiring (EIA/TIA-568B)

Pin	Pair	Wire	Color
1	2	1	white/orange
2	2	2	orange/white
3	3	1	white/green
4	1	2	blue/white
5	1	1	white/blue
6	3	2	green/white
7	4	1	white/brown
8	4	2	brown/white

10BASE-T was the first vendor-independent standard implementation of Ethernet on twisted pair wiring. However, it was in fact an evolutionary development from AT&T StarLAN which had both 1 Mbit/s and 10 Mbit/s versions. 10BASE-T is essentially StarLAN-10 with the addition of the link-beat.

In the OSI model, 10BASE-T is at the physical layer. Ethernet encompasses both addressing at the data link layer and a number of physical-layer implementations. In this model, 10BASE-T is one of the possible physical layer standards for ethernet-- some others include 10BASE2, 10BASE5, and 100BASE-TX. Network layer protocols, such as IP, do not generally need to know whether they are being hosted on 10BASE-T or not, provided they know that they are being hosted on Ethernet.

See also

• computer network
• Ethernet
• RJ-45
• 25-pair color code