MSISDN

REMORA Category: M

The MSISDN (Mobile Station – ISDN) number is the telephone number assigned to a mobile user, allowing anyone on the public switched telephone network (PSTN) to call the mobile station. It follows the ITU-T Recommendation E.164 numbering plan, which is a global standard for numbering telecommunications networks. E.164 = CC + NDN + SN
Here’s a breakdown of the components of an MSISDN or GT number:

  1. Country Code (CC): This is the first part of the MSISDN and represents the country in which the mobile station is registered. It is a numerical code assigned to each country, ensuring that mobile numbers are unique on a global scale. For example, the country code for the United States is “+1,” and for the United Kingdom, it is “+44.”
  2. National Mobile Number: The national mobile number consists of two parts:a. National Destination Code (NDC): This part of the number identifies the specific geographic area or region within the country. It helps route calls to the correct region or mobile network. The format and length of the NDC can vary by country.b. Subscriber Number (SN): The subscriber number is a unique identifier within the NDC, pointing to the individual mobile subscriber. It distinguishes one mobile user from another within the same geographic area or network.

Combining these components, an MSISDN number allows callers from anywhere in the world to reach a specific mobile user by dialing the correct country code, NDC, and subscriber number.

For example, a fictional MSISDN for a mobile user in the United States might look like this: +1 (NDC) XXX-XXXX

Where:

  • “+1” is the country code for the United States.
  • “(NDC)” represents the national destination code, which can vary depending on the specific geographic area or mobile network.
  • “XXX-XXXX” is the subscriber number, uniquely identifying the individual mobile user.

It’s important to note that the exact format and number of digits in an MSISDN may vary from country to country, but the general structure follows the E.164 numbering plan to ensure global compatibility for mobile communication.