T interface

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A T-interface or T reference point is used for basic rate access in an Integrated Services Digital Network (ISDN) environment. It is a User–network interface reference point that is characterized by a four-wire, 144 kbit/s (2B+D) user rate.

Integrated Services Digital Network set of communication standards for simultaneous digital transmission of voice, video, data, and other network services over the traditional circuits of the public switched telephone network, first defined in 1988

Integrated Services Digital Network (ISDN) is a set of communication standards for simultaneous digital transmission of voice, video, data, and other network services over the traditional circuits of the public switched telephone network. It was first defined in 1988 in the CCITT red book. Prior to ISDN, the telephone system was viewed as a way to transport voice, with some special services available for data. The key feature of ISDN is that it integrates speech and data on the same lines, adding features that were not available in the classic telephone system. The ISDN standards define several kinds of access interfaces, such as Basic Rate Interface (BRI), Primary Rate Interface (PRI), Narrowband ISDN (N-ISDN), and Broadband ISDN (B-ISDN).

In telecommunications, a user–network interface (UNI) is a demarcation point between the responsibility of the service provider and the responsibility of the subscriber. This is distinct from a network-to-network interface (NNI) that defines a similar interface between provider networks.

The kilobit is a multiple of the unit bit for digital information or computer storage. The prefix kilo- (symbol k) is defined in the International System of Units (SI) as a multiplier of 103 (1 thousand), and therefore,

Other characteristics of a T-interface are:

In computer networking, the transport layer is a conceptual division of methods in the layered architecture of protocols in the network stack in the Internet Protocol Suite and the Open Systems Interconnection (OSI) reference model. The protocols of this layer provide host-to-host communication services for applications. It provides services such as connection-oriented communication, reliability, flow control, and multiplexing.

Network Termination 1 (NT1) or Network Termination type 1 refers to equipment in an Integrated Services Digital Network (ISDN) that physically and electrically terminates the network at the customer's premises. The NT1 network termination provides signal conversion and timing functions which correspond to layer 1 of the OSI model. In a Basic Rate Interface, the NT1 connects to line termination (LT) equipment in the provider's telephone exchange via the local loop two wire U interface and to customer equipment via the four wire S interface or T interface. The S and T interfaces are electrically equivalent, and the customer equipment port of a NT1 is often labelled as S/T interface. There are many types of NT1 available.

In telecommunications, a channel service unit (CSU) is a line Bridging device for use with T-carrier that:

The T interface is electrically equivalent to the S interface, and the two are jointly referred to as the S/T interface. [2]

The S interface or S reference point, also known as S0, is a user–network interface reference point for basic rate access in an Integrated Services Digital Network (ISDN) environment, that

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Basic Rate Interface

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References

  1. ↑ PD-icon.svg This article incorporates  public domain material from the General Services Administration document "Federal Standard 1037C" .
  2. ↑ Becker, Ralph (2006-12-05). "ISDN Tutorial: Interfaces". ralphb.net. Retrieved 2014-01-22.


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