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RFC 3261 / MECHANISMS

Register a reachable contact

01

A registrar records a binding from an address-of-record to a contact URI.

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DIAGRAM§ 10 ↗
RFC 3261 · § 10EXAMPLE
3 / 3
Register a reachable contactA registrar records a binding from an address-of-record to a contact URI. Current state: Location binding.Register a reachable contactUARegistrarsip:alice@example.orgREGISTER + Contactaddress-of-record↳ current contact · expiresbinding
03
Location binding

The registrar records the accepted contact for future routing.

Protocol participantThreat or exceptionProtocol controlSimplified drawings · precise section references
WHAT CHANGED
RFC 2543RFC 3261 § 28

RFC 3261 replaces the earlier SIP specification and clarifies dialogs, transactions, routing, and registration behavior.

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KEY POINT

Registration changes location bindings rather than establishing a media call.

  • Registration changes location bindings rather than establishing a media call.
  • Bindings have expiration and are refreshed as needed.
  • Authentication policy protects registration changes.
DETAILS

The illustration is schematic. Example values are illustrative; profiles and later security guidance can add requirements.

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Diagrams simplify the RFC. Read the linked sections for complete requirements.

Privacy
All chapters in this RFC
  1. Register a reachable contact
  2. Invite through a proxy
  3. A dialog outlives a transaction
  4. Cancel a request, end a session
  5. Signaling is not the media stream
RFC 9700 / CHAPTERS

Chapters

For full details, tables, algorithms, and exceptions, read the original RFC.

RFC status and corrections ↗