Trunk 1

As Trunk 1 ( T1 , T1 or DS1 ) is referred to in the telephony the first multiplex level of the American telephone system with a data rate of 1.544 Mbit / s or 24 ISDN - data channels with 64 kbit / s. Both voice and data traffic can be handled via the individual data channels. T1 was developed by AT&T in 1957 . The specification also applies in Canada and Japan.

A complete T1 connection can be rented as a leased line and was often used to connect companies to the Internet via an Internet Service Provider (ISP). Colloquially, a T-line is often used . The faster alternative to T1 is T3 , which is often used to connect the ISP to a backbone .

The European equivalent is the primary rate connection (E1) with a data rate of around 2 Mbit / s.

The Japanese standard J1 differs from T1 only in a few details.

See also

• T1 Carrier Front End (T1FE)
• T1 Carrier Outstate (T1OS)

other connection standards:

• T3 (43.2 Mbit / s, 28 × T1)
• OC1 (51.84 Mbit / s, 33,… × T1)
• OC3 (155.52 Mbit / s, 3 × OC1)
• OC12 (622.08 Mbit / s, 4 × OC3)
• OC24 (1,244.19 Mbit / s, 2 × OC12)
• OC48 (2,488.32 Mbit / s, 2 × OC24)
• OC192 (9.6 Gbit / s, 4 × OC48)
• OC768 (38.4 Gbit / s, 4 × OC192)
• OC3072 (153.6 Gbit / s, 4 × OC768)

Web links

• http://www.t1.org - T1 Telecommunications Committee (in English)
• http://computer.howstuffworks.com/question372.htm - Howstuffworks "How does a T1 line work?" (English speaking)

Individual evidence

1. ↑ Bob Wachtel: All You Wanted to Know About T1 But Were Afraid to Ask (English)