No Audio from IP phone to IP phone

[spen2]

Hi,

I have recently set up an i2004 phone at home that connects to my works BCM400. This is set up through a VPN and all is workiing fine except a strange problem i'm having. One of my colleagues who also has an i2004 phone set up, but if we try and phone each other on our extension numbers we cannot hear anything. This only happens from IP phone to IP phone, if either of us phones someone in the office or an external number, it all works fine.

Does anyone have any ideas why this is happening and how to fix it? We only have 2 IP phones set up at the moment so haven't been able to try calling another just yet.

Thanks

Spencer

 

[biv343]

I'm guessing that you have a IP routing issue going on. Are both i2004 phones connected over VPN? Can you ping addresses on the remote network from the network that the i2004 lives on?

 

[56BelAir]

check your default gateways on each IP phone and your BCM.
A wrong or empty gateway field will cause this.

 

[jeter]

biv343 seems to be on the right track. When the call is setup they go through the system once signaling is completed the phones are end to end. Both remote sites need a vpn connection for this to work correctly. routing is probably your main issue.

“Reserve your right to think, for even to think wrongly is better than not to think at all”

CCNA,CCNP,Network+
Tek-TIP Member 19,650

 

[gwebster]

You will probably find that your VPN is configured to block incoming packets from one VPN connection to be routed out over another VPN connection.

 

[naybag]

spen2 have you been able to resolve this issue. This has been an ongoing issue with us that we haven't been able to easily resolve. We have 10 remote locations, each with an IP 2004 set. And those locations can't talk to each other. FYI, a workaround is to call the complete 10 digit DN phone number, as opposed to the extension number.

WE have to set up a VPN tunnel from each location to each of the other locations. We tried modifying the routes, with no success. Any other ideas?

 

[jbenpeter]

I have got the same issue 2 2004 connected to 2 221 contivity routers, via VPN to a BCM 400 setup as a branch tunnel. but ip to ip phones does not work.

 

[dhcommunications]

I've gotten this to work through a Contivity 1010 with remote 221's. Give each 221 a unique subnet address per site (192.168.20.1, 192.168.21.1, etc.)

Use 192.168.20.0 255.255.255.0 as the local network, and 0.0.0.0 0.0.0.0 as the remote network.

Set up the 1010 with all 0's as the local, and 192.168.20.0 as the remote.

If the BCM uses another router as the default gateway, build a static route for 192.168.0.0 that points to the Contivity 1010.

This setup should allow remote IP phones to talk to each other.

 

[ktludwig]

You need to set up a VPN tunnel between the 2 VPN routers. It's not enough that the two VPN routers have a tunnel to the BCM, there needs to be a tunnel between the 2 VPN routers as well.

 

[NewTechinTown]

We just did a hosted call center and used trunks from a 3rd party BCM to give 18 IP phones @ a local site dial tone. The problem was that even though the VPN Router had tunnels linked to both remote sites (trunks and IP phones) we could'nt get Audio until we created the tunnel between the two remote sites. The VPN router didnt know how to process the information correctly to both ends. Now An Ip phone calls through a tunnel to a bcm(host VPN) through another tunnel to another BCM where it grabs the trunk and everything works like a peach! Hope this helps.