I have just installed a voip phone into my network and I am able to use my phone as VOIP phone. I was looking at my router traffic and I noticed that as soon as I started using the voip phone the ICMP traffic just kept increasing and icreasing. The more I used the phone the more ICMP denied traffic I saw on my router. Please can somebody let me know how ICMP and VOIP are related??
Which ICMP traffic does VOIP use or need or what is going on then because the icrease in icmp traffic is definately related to the VOIP usage??
Also please can let me know the best way of securing voip in my network??
VOIP phones uses udp traffic (udp port range 16384 32767)for RTP streams. So no way its related with ICMP. You can sniff those ICMP packets and see the source and destination ip with port numbers to find who is sending it.
Not sure if this is related to the same problem, but I have just experienced a IP phone 7940 at one of our SOHO sites connected via VPN tunnel that was generating and large amount of ICMP traffic to our Unity server. I still have the ethereal capture with the source IP as the phone and the Unity server as the destination. End user turned of the phone and the ICMP traffic quit.