Configuring Linksys WRT54G Wireless Router for my home

Wed, May 4, 2005

I bought my first wireless equipment a couple of days back - A Linksys Wireless-G router model WRT54G. I had selected this model after spending a number of days poring through online reviews of various routers.

The box cost me Rs. 3550 (with bill) in Nehru Place. I immediately started working on how to place it in my network. Finally an hour back, I could figure out the right way to configure it. This was the first time I had this network scenario, and I couldn’t find any documentation on the net about how to configure it. I tried various configuration combinations and finally hit upon the fairly obvious solution. ;)

For those who have similar scenario, they can probably find some clues here.

1. I use my Linux machine to dialup using my Reliance FWP (Fixed Wireless Phone - a last-mile-wireless PSTN) phone. The Linksys router doesnt support normal PAP based dialup. It only does PPPOE. So I have to still use my Linux machine to dialup.

2. My Linux machine needs to have the same network as the rest of my LAN machines, so that they can exchange data over Netbios/SMB/Samba. In any case, having multiple subnets in such a small network is a pain.

3. I don’t want the Linksys router to route packets between machines in my LAN itself. No point in such an overhead.

4. I want DHCP to give out dynamic IP addresses to wireless clients connecting through the AP.

The following option worked for me:

1. I connected all the LAN machines including the Linux machine, totalling three, to the LAN ports on the Linksys router. Since the LAN and Wireless ports are ctually on a switch, therefore exchanging data between all these machines dont require the Linksys to route at all.

2. I left the Internet port unused.

3. I setup a DHCP server on the Linux box to give IPs to wireless clients. Actually I have set all LAN machines to take their addresses from this server too. Just hat I am giving them fixed IP addresses based on their MAC addresses from within dhcpd. This is so that I have the flexibility of onfiguring dhcpd to send the Linksys IP address instead the day I get my DSL broadband connection (Sigh). Also, if then the DSL line goes down for some reason, I an simply use the Linux machine again to dialup, and configure dhcpd to send the Linux machine IP again.

4. I also happen to have a local DNS server djbdns running, with script generated hostnames/IP addresses for all machines in the DHCP ange.

5. Configuring the Linksys router:

• I left the WAN IP address method at DHCP. This will ensure that no default route exists for the router.

• I gave a local LAN address to the inside port.

• I set a WPA password, and added MAC filtering on top of that to restrict wireless clients.

Yes, you are right. I am using the router just as a regular wireless AP 😄 . I dont need the routing features … yet.

I felt that the configuration becomes far easier if one keeps the following conceptual diagram of this box in mind.