A multi-service access node (MSAN), also known as a multi-service access gateway (MSAG), is a device typically installed in a
telephone exchange
A telephone exchange, telephone switch, or central office is a central component of a telecommunications system in the public switched telephone network (PSTN) or in large enterprises. It facilitates the establishment of communication circuits ...
(although sometimes in a roadside
serving area interface
The serving area interface or service area interface (SAI) is an outdoor enclosure or metal box that allows access to telecommunications wiring.
Alternate names
*Access point (AP)
*Cabinet (cab)
*B-box (breakout box)
*Cross box
*Cross-connect b ...
cabinet
) which connects customers' telephone lines to the
core network
A backbone or core network is a part of a computer network which interconnects networks, providing a path for the exchange of information between different LANs or subnetworks. A backbone can tie together diverse networks in the same buildi ...
, to provide
telephone
A telephone, colloquially referred to as a phone, is a telecommunications device that enables two or more users to conduct a conversation when they are too far apart to be easily heard directly. A telephone converts sound, typically and most ...
,
ISDN
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 digitalised circuits of the public switched telephone network. ...
, and
broadband
In telecommunications, broadband or high speed is the wide-bandwidth (signal processing), bandwidth data transmission that exploits signals at a wide spread of frequencies or several different simultaneous frequencies, and is used in fast Inter ...
such as
DSL
Digital subscriber line (DSL; originally digital subscriber loop) is a family of technologies that are used to transmit digital data over telephone lines. In telecommunications marketing, the term DSL is widely understood to mean asymmetric di ...
all from a single platform.
Prior to the deployment of MSANs, telecom providers typically had a multitude of separate equipment including
DSLAM
A digital subscriber line access multiplexer (DSLAM, often pronounced ''DEE-slam'') is a network device, often located in telephone exchanges, that connects multiple customer digital subscriber line (DSL) interfaces to a high-speed digital co ...
s to provide the various types of services to customers. Integrating all services on a single node, which typically
backhauls all data streams over
IP or
Asynchronous Transfer Mode
Asynchronous Transfer Mode (ATM) is a telecommunications standard defined by the American National Standards Institute and International Telecommunication Union Telecommunication Standardization Sector (ITU-T, formerly CCITT) for digital trans ...
can be more cost effective and may provide new services to customers more quickly than previously possible.
A typical outdoor MSAN cabinet consists of narrowband (
POTS), broadband (
xDSL) services, batteries with rectifiers,
optical transmission unit and copper
distribution frame
In telecommunications, a distribution frame is a passive device which terminates cables, allowing arbitrary interconnections to be made.
For example, the Main Distribution Frame (MDF) located at a telephone exchange, telephone central office te ...
.
See also
*
IMS
*
Next generation network
*
Video-ready access device
References
Telephony equipment
Digital subscriber line
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