[Serusers] Difference between URI and RURI in an Invite?

It must be sutid, but in this Invite, where is the Request-URI, is it the on in the Invite itself, of another header? INVITE sip:5263983227321073@212.23.62.147:5060 SIP/2.0..Record-Route: <sip:82.146.123.252:5070;ftag=9073921E58511927264;lr=on>..Via: SIP/2.0/UDP 82.146.123.252:5070;branch= z9hG4bK762f.696c43e1.0..Via: SIP/2.0/UDP 82.146.123.252:5065..To: <sip:3227321073@82.146.123.252;user=phone>..From: Olivier<sip:3237470305@82.146.123.252;user=phone>;tag=90 73921E58511927264..Call-ID: 9ccddde28dd1cc47cafcf074e26b4e74@82.146.123.252..CSeq: 2 INVITE..Proxy-Authorization: DIGEST algorithm=MD5,nonce="42cd00e55eed3e7b6fabd16393bbd0 4ca78816c1",realm="finalcut.be",response="8839f490e49df69ba0047cb246c2347e", uri="sip:027321073@82.146.123.252",username="3237470305"..Max-Forwards: 15..Contact: <sip:323747 0305@82.146.123.252:5065;user=phone>..Allow: INVITE,OPTIONS,BYE,CANCEL,ACK,SUBSCRIBE,NOTIFY,INFO,REFER..Supported: replaces..User-Agent: ZyXEL P2000W VoIP Wi-Fi Phone..Cont ent-Type: application/sdp..Content-Length: 299....v=0..o=TelogyUnknown0000 1928256 1928256 IN IP4 192.168.2.107..s=RTP Audio..c=IN IP4 82.146.123.252..t=0 0..m=audio 36246 RTP/AVP 18 0 8 101..a=rtpmap:18 G729/8000..a=rtpmap:0 PCMU/8000..a=rtpmap:8 PCMA/8000..a=rtpmap:101 telephone-event/8000..a=fmtp:101 0-15..a=direction:active..a=nortpproxy: yes.. Thanks, Olivier