VoIP Ethernet Capture

The Tmedia product can configure one of its VoIP Ethernet ports to do Port Mirroring. This is useful when investigating RTP, Codecs or IP Tones issues.

Warning: When configuring a port as a mirror, it is important to connect that Ethernet port directly to a host. Otherwise, it will create problem with to the Ethernet switch

Physical Setup

To do a VoIP capture it is required to:

• Connect one of the VoIP Ethernet port to a laptop with Wireshark installed and 1Gbs Network card.
• Access to the Tmedia unit using SSH.
• Access the telecom baseboard of the Tmedia using telnet.

telnet 172.31.1.1

Note: 172.31.1.1 is the default IP of the TMG's Telecom module.

Start Capturing

Once the physical setup is ready. It is possible to start capturing the RTP.

• Start Wireshark to capture the Ethernet packets with the connected laptop.
• Do one of the following command to capture packets according to your setup.

Capture VoIP0 with VoIP1

• For capturing all Ethernet packets that goes through VoIP0 with VoIP1

mv88eMonitor 0x4 0x4 3

• To stop the capture

mv88eMonitor 0 0 3

Capture VoIP1 with VoIP0

• For capturing all Ethernet packets that goes through VoIP1 with VoIP0

mv88eMonitor 0x8 0x8 2

• To stop the capture

mv88eMonitor 0 0 2