Why do IP phones/CallManager go out on port 2000 on data gateway?

[dubravko.vukmirovic]

DHCP server gives computers and IP phones IP address, data gateway, DNS. Same DHCP server gives phones IP address, DNS.

I see on CheckPoint firewall that every phone sends requests on port 2000 on data gateway. Firewall is blocking that port, but IP phones communicate normally.

Why do Ethernet Phone Port send that data???

Thanks

[adeolu_adeoye]

Hi,

Port 2000 is used by the skinny protocol. This enables the phones to communicate with Call Manager. The protocol enables Call Manager to control the IP phones in a nutshell.

Check your network setup and addressing. The only reason I can think of for your firewall to see traffic on that port through the gateway is if the phones are trying to send out requests through the firewall to a ficitious Call Manager. Obviously, the fact that the phones still work means that they are on the same network with the call manager. Therefore, traffic on port 2000 should not need to cross the firewall. Do you have multiple sites separated by the firewall?

Regards,

Ade

[dubravko.vukmirovic]

Hi

Thanks for answer, I now what port 2000 do, but I have one site, one CallManager and one network, no VLANs on switches.

Regards

Dubravko

[dubravko.vukmirovic]

Hi

I put all IP phones on seperate VLAN on layer3 switch. Cisco recomend it.

Thanks anyway

Bye

[adeolu_adeoye]

Hi,

Yeah, you're right. I just assumed that was your configuration. I have voice and data traffic on separate vlans as well. Do you still see activity on that port on the firewall?

Regards,

Ade

[dubravko.vukmirovic]

Hi Ade

No I do not see any more activity on that port.

Please can I ask one more question?

Did you ever upgrade firmware on IP phone, I have 7940 and I have read instructions on

http://www.cisco.com/univercd/cc/td/doc/product/voice/c_ipphon/sip7960/sadmin31/sipmntn.htm

Part on that page is called Dual Booting from SCCP or MGCP to Release 4.0

But it doesn’t work.

Thanks