HP-UX C SIP Stack Programmer's Guide (Novembery 2007)

Working with Transactions 111

Transaction State Machine

expires, the transaction automatically sends a 500 response. Receipt of the

PRACK and responding to it moves the transaction to the

SERVER_INVITE_PRACK_COMPLETED state.

RVSIP_TRANSC_STATE_SERVER_INVITE_PRACK_COMPLETED

While in the SERVER_INVITE_REL_PROV_RESPONSE_SENT state, the

INVITE server transaction waits for a PRACK process to be completed. The

PRACK process is handled by a separate general server transaction. When the

process is completed (PRACK request is received and responded to), the

INVITE server transaction assumes the SERVER_INVITE_PRACK-

COMPLETED state. You can continue by sending one or more provisional

responses and must finish with a final response.

RVSIP_TRANSC_STATE_SERVER_INVITE_PROXY_2XX_RESPONSE_SENT

When proxying an INVITE 2xx response with the

RvSipTransactionRespondMsg() function, the transaction sends a response

message. The transaction will then assume the

SERVER_PROXY_INVITE_FINAL_RESPONSE_SENT state. When entering

this state, the transaction timer is set to proxy2xxSentTimer.When this timer

expires, the transaction is terminated. This state is used only for a Proxy

implementation.

Note The ACK on a 2xx response to INVITE is not part of the Invite transaction.