VoIP DID or DDI number is a service/solution sold by telephone companies such as ITSPs, CLECs and ILECs to VoIP service providers and enterprises. It's even offered to end user/individual nowadays.

DID is a phone number feature used for an incoming calls and forwarding. It allows you as an outside caller to reach your desired extension number or person directly. Unlike old PBXs (Private Branch Exchange systems) an operator is not required.

DID stands for Direct Inward Dialing and...

  • ITSP stands for Internet Telephony Service Provider
  • CLECs for Competitive Local Exchange Carrier 
  • ILECs for Incumbent Local Exchange Carrier

And VoIP DID is also known as...

  • DDI (Direct Dial-In) in Europe and Oceania
  • Virtual phone Number 
  • Local phone number
  • Local access number (E.g in the case of using a calling card or phone card)
  • Call forwarding

VoIP Did numbers are very essential and becoming a must have for many businesses. It is due to many benefits and cost effectiveness that provides to companies of all size.

How VoIP DIDs work

Voxbone VoIP DID Diagram

Image Owned By Voxbone 

DID numbers work with PBXs and can be forwarded to any type of numbers where it's your VoIP number, fixed/landine and mobile phone. Let's say you are from Toronto, Canada and have a buddy in London, UK. You guyz call each other often. To save $$$, buy a DID number

in London (you pay monthly fee should cost you about $5-10 per month) and give the number to your friend. So whenever your friends want to call you, it will be a local call for him. 

When you want to use DID for business, same concept applies. You'd just need to buy bulk numbers depends on the number of employees and the size of your company. By offering this service, it'd enable you to have a physical presense in a particular city or country. 

Pros (A.K.A Advantages)

  • Low cost - the more DIDs you buy the cheaper it gets
  • Mobility & Flexibility  
  • No equipment required to deploy

Who can use VoIP DID

  • End User / Individual
  • Expats 
  • SME, Large enterprises & corporate
  • NGOs and so on...

Where to find / DID Providers

Related Articles...You May Be Interested In:

Virtual Numbers

External related link/s and resource/s:

DID Service Providers 

Virtual Number  


Business Providers 

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Residential Providers

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