The contents of the SDP "a=" field which contains a key/value pair. The contents of the SDP "b=" field which specifies the proposed bandwidth to be used by the session or media. The contents of the SDP "c=" field which contains connection data. The contents of the SDP "k=" field which is used to convey encryption keys. The contents of the SDP "m=" field with all related fields. The contents of the SDP message. The contents of the SDP "o=" field which gives the originator of the session (their username and the address of the user's host) plus a session id and session version number. Return values for the SDP functions. The contents of the SDP "t=" field which specify the start and stop times for a conference session. The contents of the SDP "z=" field which allows the sender to specify a list of time zone adjustments and offsets from the base time.