ANSI-41 and GSM MAP

GSM MAP and ANSI-41 are key protocols that utilize SS7 to allow roaming and advanced as well as more advanced capabilities. Communication between the VLR in the serving system and the HLR of the home area is facilitated by these mobile networking protocols and signaling based on a signaling protocol called Signaling System number Seven (SS7).

In GSM networks, the MAP rides on top of SS7, allowing VLR to HLR (and HLR to VLR) communications.

In non-GSM networks (such as many of those found in the United States), ANSI-41 is deployed (which also uses SS7) for HLR/VLR communications.