This INVITE came from a client device but not sure why SER 0.8.14 (i386/linux) would reject it with 400 Bad Request and there's no reason given. Any insights would help. ***************************************************** Session Initiation Protocol Request line: INVITE sip:4519@10.100.0.111:5060;transport=udp SIP/2.0 Message Header To: <sip:4519@10.100.0.222> From: "PHONE TEST"<sip:1111@172.31.1.1>;tag=5b4ae231 Via: SIP/2.0/UDP 172.31.1.20:5060;branch=z9hG4bK-d87543-ffe1a8337da8f24e89ef-1-cHA5ZGU5Mz E0ZWU3YTE3YjUzNjgxYg..-d87543- Call-ID: 4132a9661e815dd517bec43512d032db CSeq: 267297881 INVITE Contact: <sip:4AmIBQqlz52H8OKUlL_xUG_l--zuAAngOdmZbN4wa1rlMGPDB0hIkU7H3mat-JyuSGS Vy4.@172.31.1.20:5060> Max-Forwards: 69 Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER Content-Type: application/sdp Date: Thu, 15 Sep 2005 16:34:32 GMT User-Agent: Server Authorization: Digest username=&quot;testuser(a)domains.com&quot;,realm=&quot;companyX.com&quot;,algorithm=&quot;MD5&quot;,uri ="sip:4519@10.100.0.222",no nce="432993119128c2b1a32ca43b9436e2fe0bca62f0",response="e42bc4a17da0282 552265396c0eb461e",opaque="" Content-Length: 243 Session Description Protocol Session Description Protocol Version (v): 0 Owner/Creator, Session Id (o): root 27663 1963582334 IN IP4 172.31.1.20 Owner Username: root Session ID: 27663 Session Version: 1963582334 Owner Network Type: IN Owner Address Type: IP4 Owner Address: 172.31.1.20 Session Name (s): session Connection Information (c): IN IP4 172.31.1.20 Connection Network Type: IN Connection Address Type: IP4 Connection Address: 172.31.1.20 Time Description, active time (t): 0 0 Session Start Time: 0 Session Start Time: 0 Media Description, name and address (m): audio 10492 RTP/AVP 0 8 101 Media Type: audio Media Port: 10492 Media Proto: RTP/AVP Media Format: 0 Media Format: 8 Media Format: 101 Media Attribute (a): fmtp:101 0-16 Media Attribute Fieldname: fmtp Media Attribute Value: 101 0-16 Media Attribute (a): rtpmap:0 PCMU/8000 Media Attribute Fieldname: rtpmap Media Attribute Value: 0 PCMU/8000 Media Attribute (a): rtpmap:8 PCMA/8000 Media Attribute Fieldname: rtpmap Media Attribute Value: 8 PCMA/8000 Media Attribute (a): rtpmap:101 telephone-event/8000 Media Attribute Fieldname: rtpmap Media Attribute Value: 101 telephone-event/8000 Media Attribute (a): silenceSupp:off - - - - Media Attribute Fieldname: silenceSupp Media Attribute Value: off - - - - Session Initiation Protocol Status line: SIP/2.0 400 Bad Request Message Header To: <sip:4519@10.100.0.222>;tag=b27e1a1d33761e85846fc98f5f3a7e58.6a43 From: "PHONE TEST"<sip:1111@172.31.1.1>;tag=5b4ae231 Via: SIP/2.0/UDP 172.31.1.20:5060;branch=z9hG4bK-d87543-ffe1a8337da8f24e89ef-1-cHA5ZGU5Mz E0ZWU3YTE3YjUzNjgxYg..-d87543- Call-ID: 4132a9661e815dd517bec43512d032db CSeq: 267297881 INVITE Server: Sip EXpress router (0.8.14 (i386/linux)) Content-Length: 0 Warning: 392 10.100.0.111:5060 "Noisy feedback tells: pid=6024 req_src_ip=172.31.1.20 req_src_port=5060 in_uri=sip:4519@10. 100.0.111:5060;transport=udp out_uri=sip:4519@10.100.0.111:5060;transport=udp via_cnt==1" *****************************************************