# GT - Global Title A [[GT - Global Title|GT]] is an address used in the [[SCCP - Signaling Connection Control Part]] protocol to route signaling messages to their final destination. The [[GT - Global Title|GT]] can be a telephone number, an [[IMSI - International Mobile Subscriber Identity|IMSI]], or other addressing formats. A [[GT - Global Title|GT]] is often represented as an [[E.164 - international public telecommunication numbering plan|E.164]] number, used in the [[PSTN - Public Switched Telephone Network]] and some other data networks. There are three types of GT in use in mobile networks known as [[E.164 - international public telecommunication numbering plan|E.164]] ([[MSISDN - Mobile Station International Subscriber Directory Number|MSISDN]]), [[E.212]]([[IMSI - International Mobile Subscriber Identity|IMSI]]) and [[E.214]]([[MGT]]): - [[E.164 - international public telecommunication numbering plan|E.164]] ([[MSISDN - Mobile Station International Subscriber Directory Number|MSISDN]]) = [[CC - Country Code|CC]] + NDC + SN - ( Country Code+National Destination Code+Subscriber Number) e.g. 91-98-71405178 - [[E.212]]([[IMSI - International Mobile Subscriber Identity|IMSI]]) = MCC+MNC+MSIN - (Mobile Country Code+Mobile Network Code+Mobile Subscription Identification Number) e.g. 404-68-6600620186 (MTNL delhi) - [[E.214]]([[MGT]]) = combination of E.212 and E.164(CC+NDC+MSIN) (Exact combination is defined in the operators IR21 document)