WRT54GL & Cisco 7960G VoIP Phone

Question

Hello fellow Cisco users,
I use a Cisco VoIP phone, the ubiquitous 7960G IP phone, and have no problem using it with non-Cisco routers.  The phone does not seem to work with the Cisco WRT54GL router under the setup I have as explained below.
I usually connect my Cisco IP phone directly to my laptop's ethernet port giving the phone a shared internet connection.  This arrangement works fine with two non-Cisco routers I've used.  With the Cisco WRT54GL router however, the phone cannot get an IP configuration, even after opening the needed ports, leading me to believe the problem is likely to be something with the router.  I have also tried setting up a DMZ for the router without success.  The biggest problem is that the phone uses DHCP (which I also prefer) and the DMZ and port forwarding features require I set the phone's IP address.
I would greatly appreciate any thoughts on how to resolve this.
Many thanks for suggestions.
PS:  I forgot to add that the phone works (i.e. receive and make calls)  when plugged via ethernet cable into the router.  Apart from the problem of having an ethernet cable running across a room, this setup also has some features missing like date and time so calls aren't stamped.

Answer 1

I think your phone is not getting IP address when it is connected to the computer. But when you connect it directly to the modem, it works.
You can try to upgrade/re-flash the firmware on your router.
Connect the computer with the Ethernet cable to the router.
Download the latest firmware from Linksys website and save it on your computer. Open the setup page of the router. Click on Administration tab and go to Firmware upgrade sub tab. Browse the firmware file that you have already downloaded and upgrade it on your router.
After upgrading the firmware on the router, it is recommended that you should reset the router and reconfigure it. Press and hold the reset button on the router for 30 seconds. Release the reset button and wait for 30 seconds. Power cycle the router and reconfigure it.
Also try to change some advanced wireless settings on the router. Click on Wireless tab and go to Advanced wireless settings. Change the Beacon interval to 75, RTS threshold to 2307 and fragmentation threshold to 2306. Save the settings.