What Is DID?
DID is a carrier service that gives organizations multiple external numbers, each tied to an internal extension so callers can dial through directly without a receptionist.
Definition
DID (Direct Inward Dial), also known as DDI (Direct Dial-In) in Europe, allocates a block of numbers to an organization, for example 02-XXX-1000 to 02-XXX-1099 (100 numbers).
Usage
Used when staff or departments need their own numbers (Sales, Support, HR) or for marketing campaigns where each campaign has a separate DID for tracking.
Related Concepts
DID pairs with DOD (Direct Outward Dial), which lets internal users place outbound calls directly.
Frequently Asked Questions
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