Refreshing a session initiation protocol (SIP) session

摘要

In one embodiment, a session is refreshed using a message that is simplified for refresh purposes. The refresh message that is used is a message used for another purpose in a protocol (e.g., SIP). For example, a reINVITE message may be used as a refresh message. If the reINVITE message is used for its intended purpose, the reINVITE message may be used to change the characteristics of a session. This reINVITE message includes an SDP and full header such that the parameters can be properly changed. However, the reINVITE message may be used to refresh a session. This may be referred to as a simple refresh message. But, the simple refresh message does not include an SDP or any other message body. The simple refresh message includes only a reduced header. This reduces time spent building and parsing the simple refresh message.

主权项

1. A method comprising:
sending, using a first network device, a negotiation message to a second network device, wherein the negotiation message includes information indicating that a simple-refresh mechanism is supported by the first network device, wherein the simple-refresh mechanism is operable to refresh a Session Initiation Protocol (SIP) session using a first truncated form of an existing SIP message structure with session description protocol fields removed; responsive to sending the negotiation message, receiving at the first network device a response message from the second network device, wherein the response message (i) includes information indicating whether the simple-refresh mechanism is supported by the second network device and (ii) is in a second truncated form of the existing SIP message structure with the session description protocol fields removed; examining, using the first network device, the response message to determine whether the response message includes information associated with the simple-refresh mechanism; identifying, using the first network device, information associated with the simple-refresh mechanism included in the response message; and based on identifying the information associated with the simple-refresh mechanism included in the response message, determining that the simple-refresh mechanism is supported by the second network device.