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Network connectivity testing

The Network connectivity page can be used for troubleshooting issues that arise because of problems in the network between the IP VCR and a remote video conferencing device being called (or a device from which a user is attempting to call the IP VCR).

The page enables you to attempt to 'ping' another device from the IP VCR's web interface and perform a 'traceroute' of the network path to that device. The results show whether or not you have network connectivity between the IP VCR and another device. You can see from which port the IP VCR will route to that address. For a hostname, the IP address to which it has been resolved is displayed.

To test connectivity with a remote device, go to Network > Connectivity. In the text box, enter the IP address or hostname of the device to which you want to test connectivity and click Test connectivity.

For each successful 'ping', the time taken for the ICMP echo packet to reach the host and for the reply packet to return to the IP VCR is displayed in milliseconds (the round trip time). The TTL (Time To Live) value on the echo reply is also displayed.

For each intermediate host (typically routers) on the route between the IP VCR and the remote device, the host's IP address and the time taken to receive a response from that host is shown. Not all devices will respond to the messages sent by the IP VCR to analyse the route; routing entries for non-responding devices is shown as <unknown>. Some devices are known to send invalid ICMP response packets (e.g. with invalid ICMP checksums); these responses are not recognized by the IP VCR and therefore these hosts' entries are also shown as <unknown>.


Note: The ping message is sent from the IP VCR to the IP address of the endpoint that you enter. Therefore, if the IP VCR has an IP route to the given IP address, regardless of whether that route lies out of port A or port B, the ping will be successful. This feature allows the IP VCR’s IP routing configuration to be tested, and it has no security implications.

If you are unable to ping the device then check your network configuration especially any firewalls using NAT.

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