Mobile Application Part


The Mobile Application Part is an SS7 protocol that provides an application layer for the various nodes in GSM and UMTS mobile core networks and GPRS core networks to communicate with each other in order to provide services to users. The Mobile Application Part is the application-layer protocol used to access the Home Location Register, Visitor Location Register, Mobile Switching Center, Equipment Identity Register, Authentication Centre, Short message service center and Serving GPRS Support Node.

Facilities provided

The primary facilities provided by MAP are:
The Mobile Application Part specifications were originally defined by the GSM Association, but are now controlled by ETSI/3GPP. MAP is defined by two different standards, depending upon the mobile network type:
In cellular networks based on ANSI standards plays the role of the MAP a similar protocol usually called IS-41 or ANSI-41. Since 2000 it is maintained by 3GPP2 as N.S0005 and since 2004 it is named .

Implementation

MAP is a Transaction Capabilities Application Part user, and as such can be transported using 'traditional' SS7 protocols or over IP using Transport Independent Signalling Connection Control Part ; or using SIGTRAN.
Yate is a partial open source implementation of MAP.

MAP signaling

In mobile cellular telephony networks like GSM and UMTS the SS7 application MAP is used. Voice connections are Circuit Switched and data connections are Packet Switched applications.
Some of the GSM/UMTS Circuit Switched interfaces in the Mobile Switching Center transported over SS7 include the following:
There are also several GSM/UMTS PS interfaces in the Serving GPRS Support Node transported over SS7: