Agent registering

	<send retrans="500">
		<![CDATA[
			REGISTER sip:[remote_ip]:[remote_port] SIP/2.0
			Via: SIP/2.0/[transport] [local_ip]:[local_port];branch=[branch]
			To: <sip:[service]@[remote_ip]:[remote_port]>
			From: agent <sip:[service]@[remote_ip]:[remote_port]>;tag=[pid]SIPpTag00[call_number]
			Contact: sip:[service]@[local_ip]:[local_port]
			Expires: 3600
			Call-ID: [call_id]
			CSeq: [cseq] REGISTER
			Max-Forwards: 70
			Content-Type: application/sdp
			Content-Length: [len]

			v=0
			o=0123456789 53655765 2353687637 IN IP[local_ip_type] [local_ip]
			s=agent
			c=IN IP[media_ip_type] [media_ip]
			t=0 0
			m=audio [media_port] RTP/AVP 8 101
			a=rtpmap:8 PCMA/8000
			a=rtpmap:101 telephone-event/8000
			a=fmtp:101 0-15
			a=ptime:300
			a=sendrecv
			a=sendrecv

		]]>
	</send>

	<recv response="200"></recv>