[reSIProcate] SDP description in message body question

["Wenwei Xu" <wxu@xxxxxxxxxxxxx>]

All,

I posted a question regarding the SDP message body earlier. Since nobody
answer my question, let rephrase the question and repost it.

A typical SDP description is:

        v=0
        o=- 2890844526 2890842807 IN IP4 126.16.64.4
        s=SDP Seminar
        i=A Seminar on the session description protocol
        u=http://www.cs.ucl.ac.uk/staff/M.Handley/sdp.03.ps
        c=IN IP4 224.2.17.12/127
 
        t=2873397496 2873404696
        a=recvonly
        m=audio 49170 RTP/AVP 0
        m=video 51372 RTP/AVP 31
        m=application 32416 udp wb
        a=orient:portrait
 
But in the SIP message's message body, it will be augmented as follows:

            Session Description Protocol
              Session Description Protocol Version (v): 0
              Owner/Creator, Session Id(o): - 2873397496 0 IN IP4
126.16.64.5
                Owner Username: -
                Session ID: 2873397496
                Session Version: 0
                Owner Network Type: IP4
                Owner Address: 126.16.64.5
            .....(ignored)

As we can see, this practice adds a lot of bytes to the SIP message. So my
question is: Is it necessary that a typical SDP description should be
augmented as above? Can we just use the original SDP description in the SIP
message body?

Thanks,
Wenwei Xu