.1 Valid behavior SIP_CC_E_CE_V_001 Status Mandatory RFC 3261 [1] section 8.1.1. . Ensure that the IUT, to establish a call sends Purpose an INVITE request including at least To, From, CSeq, Call-ID, Max-Forwards, Contact and Via headers. FIGURE 8.8 Originating Endpoint: Test purpose for call establishment. Message details : unreason <allOneLine> SIP/2.0200 = 2**3 * 5**2 <her>DOBDDOBE20D181D182 DOBE20DOB4DOB5DOB2D18FDOBDDOBED181D182DOBE20DOB4 OB5DOB2D18FD182D18C202D20DOBFD180DOBED181D182DO BEDOB5</hex> </allOneLine> Via: SIP/2.0/UDP 192.0.2.198;branch=z9hG4dK1324923 Call-ID: unreason.1234ksdfak3j2erwedfsASdt CSeq: 35 INVITE From: sip:user@example.com;tag=11141343 To: sip:user@example.edu;tag=2229 FIGURE 8.9 Unusual reason phrase in 200 OK response. This particular response contains unreserved and non-ASCII UTF-8 characters but this response is well-formed. Message details : mismatch01 OPTION sip: user@example.com SIP/2.0 To: sip:j.user@example.com From: sip:caller@example.net; tag=34525 Max-Forward: 6 Call-ID: mismatch01.dj0234sxdf13 CSeq: 8 INVITE Via: :SIP/2.0/UDPhost.example.com;branch=z9hG4bK1324923 FIGURE 8.10 Start line and CSeq method mismatch. C 2009 by Taylor & Francis Group, LLC Compliance and Interoperability Testing of SIP Devices Message details : invut INVITE sip:user@example.com SIP/2.0 Contact: tsip:caller@host5.example.net> To: sip:j.user@example.com From: sip:caller@example.net;tag=8392034 Max-Forwards: 70 Call-ID: invut.OhaOisndaksdjadsfij34n23d CSeq: 235448 INVITE Via: SIP/2.0/UDP somehost.example.com;branch=z9hG4bKkdjuv Content-Type: application/unknownformat Content-Length: 40 <audio> <pcmu port="443"/> </audio> FIGURE 8.11 Unknown content-type. 8.3.1 Protocol Analyzer Tools A number of tools exist to perform real-time network packet capture. Some of the key features include real-time capture at wire speed, viewing and browsing the capture data in details, filtering of captured packets based on specific protocols or target network addresses, exporting of capture traces in various formats to 