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SMS Glossary


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msisdn - virtual reply numberMSISDN (Virtual Mobile Number)


There is some debate concerning what the abbreviation MSISDN refers to but the most common suggestion is “Mobile Station International Subscriber Directory Number”.


In general terms it is the phone number that relates to the SIM card in a mobile device. Each SIM card has a code known as an IMSI (International Mobile Subscriber Identity) which uniquely identifies the SIM card itself. The MSISDN identifies the network to which that SIM card is subscribed, so whilst the IMSI is fixed for the life of the SIM the MSISDN can change as different networks are subscribed to.


In the world of Online SMS the term MSISDN is often used to refer to a Virtual Mobile Number or VMN. The Virtual Mobile Number has the same format as a local mobile telephone number, e.g. in the UK it is an 11-digit number in the format 07nnnnnnnnn. These are sometimes referred to as Virtual Reply Numbers or VRNs or SMS Long Numbers. But MSISDN does actually refer to any mobile number not just those used for SMS and so the term is being increasingly replaced with one of the more specific alternatives.


So effectively a Virtual Mobile Number is a special type of MSISDN used to receive SMS messages direct to your PC through the Fastsms system. You can also send from this number so your recipients can reply easily back to your Fastsms inbox. From here it can be forwarded to another mobile number, and/or to an email address and/or to a url whereby it can be integrated with third party software.


In Fastsms the Virtual Mobile number can also make use of keywords to segregate resonses and trigger specific auto responders for different keywords.

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