Creating and using a SipMessage

From reSIProcate

Contents 1 Components 2 stuff 2.1 Computing 2543 transaction ids. 3 Variants

[edit] Components

Headers

Uris

Bodies

Parameters

Extension Headers

Extension Parameters

[edit] stuff

[edit] Computing 2543 transaction ids.

Transaction ids are used to map a message to the state of its transaction.

3261 uses assigned transaction ids carried in the branch parameter of the Via. 2543 uses a transaction id that is computed from the message.

The 2543 transaction is a hash of:

• top Via
  • protocolName
  • protocolVersion
  • transport
  • sentHost
  • sentPort
  • commutativeParameterHash (not sensitive to the order of the paramters)
• From tag
• To tag (if non-invite request)
• Call-Id
• method (INVITE if ACK or CANCEL)

Once computed, the 2543 transaction id is cached on the message.

[edit] Variants

SipFrag

Embedded Headers