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VCT Advanced Tab
This section is used for diagnostic purposes to instruct the Vertex is set to dump raw network packets
to the program. The VCT can analyze SIP packets to show the call flow and other detailed data that
may be used to configure the Vertex. It also saves these packets into a file that can be read by
Wireshark, a packet analyzer application.
During the raw packet dump, the normal processing of Caller ID records is automatically turned off.
Consequently, VCT and other applications will not show standard call records.
VoIP Signaling Format.
Normally, the SIP Invite header includes the Session Description
Protocol (SDP). The Vertex requires information from the SDP to process call records. A few VoIP
providers do not transmit SDP on inbound calls until a phone is answered (SIP 200 OK header).
The "Slow-Start SDP & Frag.TCP" format option is available for these providers. This same option
should be used when fragmented TCP SIP headers are delivered by the provider. Analyzing a
packet capture with Wireshark will determine whether this optional signaling format is required.