Extension
Was ist Extension?
Dieser Eintrag liegt derzeit nur auf Englisch vor.
An extension is a short internal number — typically three to five digits — assigned to a person, department, or ring group on a PBX or cloud phone system, letting colleagues reach each other by dialing a short internal code instead of a full external phone number. A DID number can be mapped to an extension so external callers reach it directly, while internal calls between extensions never leave the phone system.
More detail
A worked example: a front-desk receptionist answers an outside call, glances at the busy-lamp field to see that support agent 204 is free, and dials the three-digit extension to transfer. No external number is dialed and there is no hunt through a contact directory — the call stays inside the phone system.
An extension is distinct from a DID, and the two are commonly mapped together: the extension is the internal dial-plan address colleagues dial, while the DID is the external phone number an outside caller dials to reach that same destination. Extensions are usually assigned in logical blocks per department or location so staff can remember and dial a colleague's number internally.
On Orbit, an extension is the SIP identity — a username, password, and optional short extension number — that a person or device uses to place and receive calls. One extension powers several ways to answer it: the in-browser softphone, a desktop or mobile SIP app, or a physical desk phone provisioned over zero-touch provisioning, all created and maintained under the Voice → Extensions surface.
Häufige Fragen
- Is an extension the same thing as a phone number?
- No — an extension is a short internal code used to reach a colleague within the same phone system, while a phone number (or DID) is what an external caller dials; the two are commonly mapped together but serve different purposes.
- Can external callers dial an extension directly?
- Not the extension itself, but a DID number mapped to that extension lets an external caller reach it directly, or an auto-attendant can prompt callers to enter an extension to be routed internally.
See also
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