Unable to connect Cisco IP phone 8841 through MRA using CiscoLinksys WRT54G2 router

[orellanas]

Hi Everyone,

When I connect my IP phone 8841 directly to cable modem (Motorola), the Phone get registered in CUCM. but when I connect the IP Phone with WRT54G2 in between, the Cisco IP phone does not get registered in CUCM.

It says "verify your service domain and internet connectivity". 

I already did a lot of changes in the Linksys router but the same issue, can some one can help me with this issue ? 

Thanks in advance, 

Orellana

[Jaime Valencia]

Review a PRT from the device and logs from EXP-E, but that most usually means either ports are blocked or maybe something like SIP ALG is causing some issue.

[orellanas]

Sip Alg is enable in the firewall that is in the front of the exp-e. 

but why the phone gets registered when I plug it in the home modem? 

and then when I connect the CiscoLinksys WRT54G2 to the modem and connect the phone to the CiscoLinksys WRT54G2 the registration doesn't get completed ? 

That CiscoLinksys does not have to many options to play with, talking about option to grant full open port for testing purpose. 

Thanks for responding, 

Orellanas