SIP Session Description Codes

Session description
     v= (protocol version)
     o= (owner/creator and session identifier)
     s= (session name)
     i=* (session information)
     u=* (URI of description)
     e=* (email address)
     p=* (phone number)
     c=* (connection information - not required if included in all media)
     b=* (bandwidth information)
One or more time descriptions (see below)
     z=* (time zone adjustments)
     k=* (encryption key)
     a=* (zero or more session attribute lines)
Zero or more media descriptions (see below)
Time description
     t= (time the session is active)
     r=* (zero or more repeat times)
Media description
     m= (media name and transport address)
     i=* (media title)
     c=* (connection information - optional if included at session-level)
     b=* (bandwidth information)
     k=* (encryption key)
     a=* (zero or more media attribute lines)