Glossary
DID number
Definition
A Direct Inward Dialing number reaches a specific endpoint directly, without a switchboard; each one is individually routable.
Why it matters
What retail calls a virtual number, wholesale calls a DID. Carriers allocate DID blocks to providers, who resell individual numbers. These are the ranges a provider means when it says "we hold ranges".
Related reading
Sources
- ITU-T Recommendation E.164 — The international public telecommunication numbering plan · International Telecommunication UnionCountry calling codes, national significant number lengths, number structure
- ITU-T E.164 national numbering plans (Operational Bulletin annex) · International Telecommunication UnionPer-country numbering plans, mobile ranges, trunk prefixes
Part of the HushSMS glossary — 18 terms defined.