The mobile switching station, abbreviated as MSC Server or MSS, is a 2G

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 ...

element which controls the

network switching subsystem Network switching subsystem (NSS) (or GSM core network) is the component of a GSM system that carries out call out and mobility management functions for mobile phones roaming on the network of base stations. It is owned and deployed by mobi ...

elements. Alternatively or adaptively, MSS can be used in

GSM The Global System for Mobile Communications (GSM) is a family of standards to describe the protocols for second-generation (2G) digital cellular networks, as used by mobile devices such as mobile phones and Mobile broadband modem, mobile broadba ...

networks as well, if the manufacturer has implemented support for GSM networks in the MSS. Since an immediate upgrade of existing GSM network to 3G is not viable due to various issues like handset incompatibilities and high expenditure, most manufacturers do implement GSM support in MSS. In fact, MSS along with other 3G network elements such as

media gateway A media gateway is a translation device or service that converts media streams between disparate telecommunications technologies such as POTS, SS7, Next Generation Networks ( 2G, 2.5G and 3G radio access networks) or private branch exchange ( ...

(MGW), can be configured to support GSM network exclusively and can be considered as an upgraded version of existing GSM

mobile switching centre Network switching subsystem (NSS) (or GSM core network) is the component of a GSM system that carries out call out and mobility management functions for mobile phones roaming on the network of base stations. It is owned and deployed by mobile ...

s. The MSC Server is standards-based and communicates with other distributed elements using industry open standards such as

media gateway control protocol The Media Gateway Control Protocol (MGCP) is a telecommunication protocol for signaling and call control in hybrid voice over IP (VoIP) and traditional telecommunication systems. It implements the media gateway control protocol architecture f ...

, megaco/ H.248,

Session Initiation Protocol The Session Initiation Protocol (SIP) is a signaling protocol used for initiating, maintaining, and terminating communication sessions that include voice, video and messaging applications. SIP is used in Internet telephony, in private IP telepho ...

, M2UA and

M3UA M3UA is a communication protocol of the SIGTRAN family, used in telephone networks to carry signaling over Internet Protocol (IP). M3UA enables the SS7 protocol's User Parts (e.g. ISUP, SCCP and TUP) to run over virtually any network techno ...

. The MSC server incorporates industry standards as defined by

ETSI The European Telecommunications Standards Institute (ETSI) is an independent, not-for-profit, standardization organization operating in the field of Information and communications technology, information and communications. ETSI supports the de ...

, ITU,

3GPP The 3rd Generation Partnership Project (3GPP) is an umbrella term for a number of standards organizations which develop protocols for mobile telecommunications. Its best known work is the development and maintenance of: * GSM and related 2G and ...

and

3GPP2 The 3rd Generation Partnership Project 2 (3GPP2) was a collaboration between telecommunications associations to make a globally applicable third generation (3G) mobile phone system specification within the scope of the ITU's IMT-2000 project. ...

and other leading standard bodies. The MSS supports the regulatory environment set by governing bodies via its support for E911, CALEA/legal intercept, wireless and

local number portability Local number portability (LNP) for fixed lines, and full mobile number portability (FMNP) for mobile phone lines, refers to the ability of a "customer of record" of an existing fixed-line or mobile telephone number assigned by a local exchange c ...

, TTY/TTD, and Number Pooling requirements. Alternatively MSS is also called an MTS-U (Motorola telephony soft-switch) in

Motorola Motorola, Inc. () was an American multinational telecommunications company based in Schaumburg, Illinois. It was founded by brothers Paul and Joseph Galvin in 1928 and had been named Motorola since 1947. Many of Motorola's products had been ...

terminology, and as MSC-S in

Ericsson (), commonly known as Ericsson (), is a Swedish multinational networking and telecommunications company headquartered in Stockholm, Sweden. Ericsson has been a major contributor to the development of the telecommunications industry and is one ...

terminology. MSC server functionality enables split between

control plane In network routing, the control plane is the part of the router architecture that is concerned with establishing the network topology, or the information in a routing table that defines what to do with incoming packets. Control plane functions, ...

(signalling) and user plane (bearer in network element called a media gateway), which guarantees better placement of network elements within the network. MSC server and MGW makes it possible to cross-connect circuit switched calls switched by using IP, ATM AAL2 as well as TDM.

References

3GPP TS 23.205
* {{Reflist Telecommunications equipment Telecommunications infrastructure Mobile telecommunications GSM standard