Network switching subsystem

<p>Network switching subsystem  (NSS) (or GSM core network) is the component of a <a href="/facts/GSM/Sw8QYaLE">GSM</a> system that carries out <a href="/facts/Telephone_exchange/PaRpGm8I">call out</a> and <a href="/facts/Mobility_management/YDFn4RQL">mobility management</a> functions for <a href="/facts/Mobile_phones/H3EcqD9h">mobile phones</a> <a href="/facts/Roaming/SEfznzxD">roaming</a> on the <a href="/facts/Base_Station_subsystem/aFl0pNva">network of base stations</a>. It is owned and deployed by <a href="/facts/Mobile_phone_operator/3cGaXm1Q">mobile phone operators</a> and allows mobile devices to communicate with each other and <a href="/facts/Telephone/P7uEgWQX">telephones</a> in the wider <a href="/facts/Public_switched_telephone_network/eVrCTDU7">public switched telephone network</a> (PSTN). The architecture contains specific features and functions which are needed because the phones are not fixed in one location.
</p><p>The NSS originally consisted of the circuit-switched <a href="/facts/Core_network/EondGP5q">core network</a>, used for traditional <a href="/facts/GSM_services/9oCDh5Tv">GSM services</a> such as voice calls, <a href="/facts/Short_message_service/kacRfW0X">SMS</a>, and <a href="/facts/Circuit_Switched_Data/AMm6gVuf">circuit switched data</a> calls. It was extended with an overlay architecture to provide packet-switched data services known as the <a href="/facts/GPRS_core_network/Ju1sjTls">GPRS core network</a>. This allows GSM mobile phones to have access to services such as <a href="/facts/Wireless_Application_Protocol/UxhCWfnv">WAP</a>, <a href="/facts/Multimedia_Messaging_Service/Pg5CvwLx">MMS</a> and the <a href="/facts/Internet/Xw1rVvJU">Internet</a>.
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Network switching subsystem open-in-new

Network switching subsystem