Cisco Systems IP phone 7960 manual SIP Call Flows

A P P E N D I X B

SIP Call Flows

SIP uses six request methods:

•INVITE—Indicates a user or service is being invited to participate in a call session.

•ACK—Confirms that the client has received a final response to an INVITE request.

•BYE—Terminates a call and can be sent by either the caller or the callee.

•CANCEL—Cancels any pending searches but does not terminate a call that has already been accepted.

•OPTIONS—Queries the capabilities of servers.

•REGISTER—Registers the address listed in the To header field with a SIP server.

The following types of responses are used by SIP and generated by the Cisco SIP gateway:

•SIP 1xx—Informational Responses

•SIP 2xx—Successful Responses

•SIP 3xx—Redirection Responses

•SIP 4xx—Client Failure Responses

•SIP 5xx—Server Failure Responses

•SIP 6xx—Global Failure Responses

	Cisco SIP IP Phone 7960 Administrator Guide
78-10497-02		B-1