What is a DID Number

What is a DID (Direct Inward Dialing) Number?

A DID number (sometimes referred to as a virtual number) is a local telephone number for any particular country or city. These numbers can then forwarded to a regular PSTN telephone, Voice over IP (VoIP), SIP, H.323, IAX, Skype, MSN or Google Talk anywhere in the world.

Typically a DID is used to provide local telephone numbers for customers worldwide, or to provide local access from regular telephones to non-PSTN destinations such as VoIP.

Tha advantages and uses of DID numbers include:

1. International and long distance telephone calls are made with the caller only paying local call rates. For example, your family lives in Moscow, Russia but you live in London, England. You would like your family to be able to phone you, but the long distance rates from Russia are very costly. If you purchase a Moscow DID, anyone dialing that local number in Moscow would connect to your phone in London, but they would pay only local phone rates.

2. You are able to add telephone numbers to your phone line so that you are no longer restricted to one telephone number per line. For example, you live in London, England but you have family in Moscow, London and Beijing. You if you purchase DIDs in Moscow, London and Beijing, then anyone dialing those local numbers would connect to your phone in London.

3. Conventional telephone calls may be terminated at non-PSTN devices if desired, such as VoIP and Skype. This has particular relevance for VoIP communications, as it allows people connected to the traditional PSTN network to call people connected to VoIP networks.

There are many additional uses for local DID numbers. For example, consider the issue of privacy. If users place classified advertisements in a newspaper and they wish prospective buyers to contact them without publishing their own, private telephone number, a temporary local number could be provided by the newspaper.