MSISDN - definition and examples


MSISDN is one of the most important technical terms in telecommunication field. This is acronym from Mobile Station International Subscriber Directory Number. Before we explain the full meaning of the importance of this number, we will give in short several other telecom entities.


MSC - Mobile Switching Centre and central part of telecom system on network layer. The MSC Server is standards-based and communicates with other distributed elements using industry open standards such as media gateway control protocol. In mobile communications , switch is mechanism which established wireless communication channel, between two involved parties. Today, only little number of vendors produce switches: ZTE, Huawei,Siemens, Motorola, Ericsson and every of them is suported with several billing systems.
BSC - Base Station Controllers
BTS - Base Transceiver Stations
HLR - Home Location Register is a central database that contains details of each subscriber that is authorized on core network.
VLR - Visitor Location Register is a temporary database of the subscribers who have roamed into the particular network area.

The HLRs store details of every SIM card issued by the mobile phone operator. Each SIM has a unique identifier called an IMSI which is the primary key to each HLR record. The next important items of data associated with the SIM are the MSISDNs, which are the telephone numbers used by mobile phones to make and receive calls. So, primary goal of this number is for making and receiving voice calls and SMS, but it is possible for a SIM to have other secondary MSISDNs associated with it for fax and data calls. This mean, that those number is also a primary key to the HLR record. The HLR data is stored for as long as a subscriber remains with the mobile phone operator.
Examples of other data stored in the HLR against an IMSI record is:
- GSM services: Voice, Fax, SMS, MMS
- GPRS settings to allow the subscriber to access packet services.
- Current location of subscriber (VLR and serving GPRS support node/SGSN).
- Call divert and forwarding applications

Definition: MSISDN is primary key to the HLR record number with maximum 15 digits without prefixes.
Example, one number in America
MSISDN: 13109976224

CC 1 United States of America - Country Code
NDC 310 California - National destination code
SN 9976224 Sasa Divac - Customer or subscriber code
NDC: National Destination Code , for California in this example is 310. Check and inform us is this treue?
SN: Subscriber Number

List of international country calling codes. On this list, national destination calling codes from entire word are given.

Format definition:
In GSM standard 1800, this number is built up as
MSISDN = CC + NDC + SN
CC = Country Code
NDC = National Destination Code
SN = Subscriber Number


In the GSM standard PCS 1900, format has next value
MSISDN = CC + NPA + SN
CC = Country Code
NPA = Number Planning Area
SN = Subscriber Number


With simple words, this is everyday used number when we call somebody on its mobile phone. In situation, when you are asking for number of mobile phone from some nice and pretty lady, you are looking for her MSISDN . If you need more details, please contact us.





Sponsor of this article is Telecom Billing Systems Blog Telecom Rating and Billing Blog