DID (Direct Inward Dialing) Number
Short answer: A DID, short for direct inward dialing, is a phone number that routes incoming calls directly to a specific line, extension or SIP account instead of through a shared switchboard. In VoIP, DID is the common name for any real phone number delivered to you over SIP, and each ZuteSIP number works as one.
DID started as a way for companies to give every desk its own number without renting a separate line per desk. Today it is the standard term VoIP providers use for the numbers they supply.
Definition
A DID is a public number that the provider maps to a destination on your side. The number can be local, mobile or toll-free; DID describes how it is delivered, not its type.
How it works
When someone dials the number, the phone network hands the call to the provider, which sends it over SIP to the registered account or trunk. A PBX then reads the dialled number and routes the call to the right extension, queue or menu.
How a DID call is delivered
| Stage | What happens |
|---|---|
| Caller dials | The phone network hands the call to the provider |
| Provider | Sends the call over SIP to the registered account or trunk |
| PBX | Reads the dialled number and routes the call |
| Destination | An extension, queue or menu |
How it applies to ZuteSIP
- Real mobile, local and toll-free numbers in 181 countries
- SIP username and password per number
- Unlimited incoming calls and SMS, plus 500 outgoing SMS and 1,000 outgoing minutes per month
- Call forwarding to any phone and a browser web dialer
- From $1.80 per month billed yearly ($21.60 per year), no setup fee
Related terms
- SIP trunk
- PBX
- Local number
- E.164
Frequently asked questions
Is a DID a virtual number?
The terms overlap. A DID is a real number delivered over the internet, which is why people often call it a virtual number.
Can a DID receive SMS?
It depends on the number. Every ZuteSIP number includes unlimited incoming SMS, shown in the dashboard inbox.
Can I route a DID to my PBX?
Yes. Register the number's SIP credentials in Asterisk, FreePBX, 3CX or another SIP-compliant PBX.
Can I port my existing number in as a DID?
No. Number porting is not part of the service; you choose a new number instead.