DID stands for direct inward dialing (in the UK and parts of Europe, DDI: direct dial-in). It began as a way for a company with a few physical lines to give every employee their own number. Today a DID is usually a number supplied by a carrier over a SIP trunk or by a cloud platform, and it can be routed anywhere: a desk phone, a softphone, a queue, an IVR or another system.
DIDs come in several types, each with its own rules on who may hold them and how they may be used:
- Local (geographic) numbers, tied to an area code
- Mobile numbers
- National (non-geographic) numbers
- Toll-free numbers, free for the caller
- Shared-cost and premium-rate numbers, where the caller pays a set rate or a surcharge
Numbers are a regulated, scarce resource. In France and Belgium, the regulators (ARCEP and BIPT) set conditions of use for each category, and breaching them can lead to the numbers being withdrawn. Providers therefore verify who the customer is before allocating numbers.
OVOKY offers seven types of phone numbers: local, mobile, national, toll-free, shared cost, verified (NPV) and premium. They route to a softphone or SIP trunk, to OVOKY inbound campaigns or to your own PBX by IP. Bulk numbers allocates whole ranges to a subscription, with voicemail on every number.