title: SIP Invite content-length
body: <p>I'm developing a SIP provider application.I use transport UDP.And I have a Questions,
  I sending a Invite message SIP Server.</p>
  
  <pre><code>INVITE sip:102@192.168.1.33 SIP/2.0
  Via: SIP/2.0/UDP 192.168.1.33:5001;branch=z9hG4bK9232c352-a28c-4467-988e-8027e0031209;rport
  To: &lt;sip:102@192.168.1.33&gt;
  From: "101"&lt;sip:101@192.168.1.33:5060&gt;;tag=rkktjbvq
  CSeq: 1 INVITE
  Call-ID: lrfnpvlvrbojabxnuldgejvncshccjpwsfxsobpcpmjrnsvkeh
  Max-Forwards: 70
  Contact: &lt;sip:101@192.168.1.33:5001&gt;
  User-Agent: Iconium
  Content-Type: application/sdp
  Content-Length: 849
  
  v=0
  o=101 940412967 940412967 IN IP4 192.168.1.33
  s=Ozeki VoIP SIP SDK
  c=IN IP4 192.168.1.33
  t=0 0
  m=audio 5003 RTP/AVP 8 0 101 98 9 3 100 97 103 15 4 104 105 106 107 18
  a=rtpmap:8 PCMA/8000
  a=rtpmap:0 PCMU/8000
  a=rtpmap:101 telephone-event/8000
  a=rtpmap:98 iLBC/8000
  a=fmtp:98 mode=30
  a=rtpmap:9 G722/8000
  a=fmtp:9 bitrate=64000
  a=rtpmap:3 GSM/8000
  a=rtpmap:100 SPEEX/16000
  a=rtpmap:97 SPEEX/8000
  a=rtpmap:103 L16/8000
  a=rtpmap:15 G728/8000
  a=rtpmap:4 G723/8000
  a=rtpmap:104 G726-16/8000
  a=rtpmap:105 G726-24/8000
  a=rtpmap:106 G726-32/8000
  a=rtpmap:107 G726-40/8000
  a=rtpmap:18 G729/8000
  a=fmtp:18 annexb=no
  a=sendrecv
  m=video 5005 RTP/AVP 102 99 34
  a=rtpmap:102 H263-1998/90000
  a=fmtp:102 QCIF=1;CIF=1
  a=rtpmap:99 H264/90000
  a=fmtp:99 packetization-mode=1
  a=rtpmap:34 H263/90000
  a=fmtp:34 QCIF=1;CIF=1
  a=sendrecv
  </code></pre>
  
  <p>Everything is okay.And SIP Server response with Proxy-Authenticate</p>
  
  <pre><code>SIP/2.0 407 Proxy Authentication Required
  Via: SIP/2.0/UDP 192.168.1.33:5001;branch=z9hG4bK9232c352-a28c-4467-988e-8027e0031209;rport=5001
  Proxy-Authenticate:Digest nonce="414d535c05ab5fd821:79225947c170510b155be0828d92e7e4", algorithm=MD5, realm="3CXPhoneSystem"
  To: &lt;sip:102@192.168.1.33&gt;;tag=d92fe85a
  From: "101"&lt;sip:101@192.168.1.33:5060&gt;;tag=rkktjbvq
  Call-ID: lrfnpvlvrbojabxnuldgejvncshccjpwsfxsobpcpmjrnsvkeh
  CSeq: 1 INVITE
  User-Agent: 3CXPhoneSystem 10.0.23053.0
  Content-Length: 0
  </code></pre>
  
  <p>And I send Authanticate with ACK;</p>
  
  <pre><code>INVITE sip:102@192.168.1.33 SIP/2.0
  Via: SIP/2.0/UDP 192.168.1.33:5001;branch=z9hG4bKaaf896d5-bd08-48f2-8e3d-0cf043e8324e;rport
  To: &lt;sip:102@192.168.1.33&gt;
  From: "101"&lt;sip:101@192.168.1.33:5060&gt;;tag=rkktjbvq
  CSeq: 2 INVITE
  Call-ID: lrfnpvlvrbojabxnuldgejvncshccjpwsfxsobpcpmjrnsvkeh
  Max-Forwards: 70
  Contact: &lt;sip:101@192.168.1.33:5001&gt;
  User-Agent: Iconium
  Content-Type: application/sdp
  Proxy-Authorization:Digest username="101", realm="3CXPhoneSystem", nonce="414d535c05ab5fd821:79225947c170510b155be0828d92e7e4", response="8592afb1b7f3440afd9607dc3db588cb", uri="sip:102@192.168.1.33", algorithm=MD5
  Content-Length: 849
  
  v=0
  o=101 940412967 940412967 IN IP4 192.168.1.33
  s=Ozeki VoIP SIP SDK
  c=IN IP4 192.168.1.33
  t=0 0
  m=audio 5003 RTP/AVP 8 0 101 98 9 3 100 97 103 15 4 104 105 106 107 18
  a=rtpmap:8 PCMA/8000
  a=rtpmap:0 PCMU/8000
  a=rtpmap:101 telephone-event/8000
  a=rtpmap:98 iLBC/8000
  a=fmtp:98 mode=30
  a=rtpmap:9 G722/8000
  a=fmtp:9 bitrate=64000
  a=rtpmap:3 GSM/8000
  a=rtpmap:100 SPEEX/16000
  a=rtpmap:97 SPEEX/8000
  a=rtpmap:103 L16/8000
  a=rtpmap:15 G728/8000
  a=rtpmap:4 G723/8000
  a=rtpmap:104 G726-16/8000
  a=rtpmap:105 G726-24/8000
  a=rtpmap:106 G726-32/8000
  a=rtpmap:107 G726-40/8000
  a=rtpmap:18 G729/8000
  a=fmtp:18 annexb=no
  a=sendrecv
  m=video 5005 RTP/AVP 102 99 34
  a=rtpmap:102 H263-1998/90000
  a=fmtp:102 QCIF=1;CIF=1
  a=rtpmap:99 H264/90000
  a=fmtp:99 packetization-mode=1
  a=rtpmap:34 H263/90000
  a=fmtp:34 QCIF=1;CIF=1
  a=sendrecv
  </code></pre>
  
  <p>And Sıp server response with</p>
  
  <pre><code>SIP 2.0/400 Bad Content-Length(larger than datagram)
  </code></pre>
  
  <p>But in Ozeki Voip SDK , 
  while content-length=851 everything is okay.(using UDP transport)</p>
  
  <p>How can I do for this?Where is the my problem?</p>
  
  <p><strong>Edit:</strong>
  My UDP client:</p>
  
  <pre><code> private void SendSIPMessage(string mesaj, bool korumalı)
          {
  
              IPEndPoint remotendpoint = new IPEndPoint(IPAddress.Any, port);
              UdpClient udpClient = new UdpClient();
              try
              {
                  udpClient.Connect("192.168.1.33", 5060);
                  Byte[] sendBytes = Encoding.ASCII.GetBytes(mesaj);
                  udpClient.Send(sendBytes, sendBytes.Length);
                  string receivedMessage = string.Empty;
                  Byte[] receiveBytes = udpClient.Receive(ref remotendpoint);
                  receivedMessage = Encoding.ASCII.GetString(receiveBytes);
                  label1.Text += receivedMessage + "\n";
  
          }
  </code></pre>