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MSISDN

Unique subscription identifier in a mobile network

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MSISDN (/ˈɛm ɛs ɛs d ɛn/) is a number uniquely identifying a subscription in a Global System for Mobile communications or a Universal Mobile Telecommunications System mobile network. It is the mapping of the telephone number to the subscriber identity module in a mobile or cellular phone. This abbreviation has several interpretations, the most common one being "Mobile Station International Subscriber Directory Number".

The MSISDN and international mobile subscriber identity (IMSI) are two important numbers used for identifying a mobile subscriber. The IMSI is stored in the SIM (the card inserted into the mobile phone), and uniquely identifies the mobile station, its home wireless network, and the home country of the home wireless network. The MSISDN is used for routing calls to the subscriber. The IMSI is often used as a key in the home location register ("subscriber database") and the MSISDN is the number normally dialed to connect a call to the mobile phone. A SIM has a unique IMSI that does not change, while the MSISDN can change in time, i.e. different MSISDNs can be associated with the SIM.

The MSISDN follows the numbering plan defined in the International Telecommunication Standard Sector recommendation E.164.

01Abbreviation

Depending on source or standardization body, the abbreviation MSISDN can be written out in several different ways. These are today the most widespread and common in use.

Organization Meaning Source
3GPP
ITU
OMA
Mobile Subscriber ISDN Number Vocabulary for 3GPP Specifications (new)
ITU-T Rec. Q.1741-4 (10/2005)
Dictionary for OMA Specifications
CSPS
ITU
GSMA
Mobile Station International ISDN Number(s) MSISDN Format and Details
ITU-T Rec. Q.1741-4 (10/2005)
Mobile Terms & Acronyms
ITU Mobile International ISDN Number Vocabulary of Switching and Signalling Terms

02MSISDN format

The ITU-T recommendation E.164 limits the maximum length of an MSISDN to 15 digits. 1-3 digits are reserved for country code. Prefixes are not included (e.g., 00 prefixes an international MSISDN when dialing from Sweden). Minimum length of the MSISDN is not specified by ITU-T but is instead specified in the national numbering plans by the telecommunications regulator in each country.

In GSM and its variant DCS 1800, MSISDN is built up as

MSISDN = CC + NDC + SN
CC = Country Code
NDC = National Destination Code, identifies one or part of a PLMN
SN = Subscriber Number

In the GSM variant PCS 1900, MSISDN is built up as

MSISDN = CC + NPA + SN
CC = Country Code
NPA = Number Planning Area
SN = Subscriber Number

The country code identifies a country or geographical area, and may be between 1-3 digits. The ITU defines and maintains the list of assigned country codes.

3N4N5N6N7N8

CC/ISD Code CCC (Example: 880) Bangladesh
NDC/NPA Code XX (Example: 15) As allocated by the Government of Bangladesh:
Teletalk: 015
Grameenphone: 017 & 013
Banglalink: 019 & 014
Robi: 018 & 016
SN N1N2N3N4N5N6N7N8
(example: 00121121)

For further information on the MSISDN format, see the ITU-T specification E.164.

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Sources and credits

This article is adapted from the Wikipedia article MSISDN, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

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