Setup for the WRT54G is similar to that of Linksys' other current routers. You can run a Windows-only setup utility that walks you through choosing a WAN type and other setup steps, or go directly to the built-in web-based admin interface, which was my choice for setup.
Since the WRT54G comes set to 192.168.1.1 as its factory default and built-in DHCP server enabled, all you'll need to do is plug in a client that's set to obtain its IP address information automatically, maybe do a DHCP release / renew (or reboot your client computer), and enter the default password into the login box that pops up. If all goes well, you'll get the main Setup screen shown in Figure 3.
Figure 3: Setup screen
The interface follows Linksys' recent trend toward putting most of the stuff that you need to futz with for a basic setup on one screen, in this case the Internet (WAN), router LAN address (in case you need to get the router in tune with an existing LAN addressing scheme), and basic Wireless settings.
Also in keeping with trying to prevent user information overload, the Internet Configuration Type selector automatically refreshes the browser screen to present settings appropriate to the choices of Automatic Configuration - DHCP, Static IP, PPPoE, and PPTP Internet connection types. The one curious choice was not having the MAC address cloning feature needed for many broadband ISPs on this main Setup page. Instead, you'll need to click over to the System tab if cloning is what you need to do.
Figure 4: System screen
The Wireless settings here are just the basics, except for the (E)SSID Broadcast Enable/Disable, which prevents your WRT54G from showing up automatically in wireless client applications (such as WinXP's "Available Wireless Networks") that show in-range AP's.
I was glad to see that Linksys included Disable as one of the Wireless Modes, since the ability to shut off the radio is a definite plus for security purposes. I'll describe what the Mixed and G-Only modes do in the Wireless performance section later.
The interface is generally quick, with quick mini-reboots needed to get the changes you make on each page to take. Multiple admin logins are allowed, with no warning given when two or more admins log on. Once you're logged in, there's no idle timeout, and you just need to remember to quit your browser when you're done, because there's no logout button.
One feature that I liked a lot involved the Remote Management feature. Enabling this for the first time popped up a message that told you that you were going to need to change the router's default password, then sent you to the Security screen to make the change. This is something that's very important, since default router passwords are so widely known.
Without it, an unsuspecting (or lazy) user could enable remote management without changing the password and expose their router - and all the LAN machines behind it - to control by anyone on the Internet.
You can also change the port used for remote management, which I'd advise doing since the default port of 8080 is included in just about every port scan that hits your WAN IP address on a (too) frequent basis.
Linksys doesn't actually specify whether the router is NAT or SPI based. From the trouble that I had running the QCheck UDP streaming tests, however, I'd say that the product is mostly NAT based, but with some SPI going on.
Although the admin screens for Port Forwarding and Filtering should be familiar to Linksys devotees, the functions that are actually implemented come up a little short vs. other members of Linksys' router product line. For example, Figure 5 shows the Port Forwarding interface.
Figure 5: Port Forwarding
If you look closely you'll note that the Port Triggering button is missing, even though it's described in the User Guide. When I asked Linksys about this, they said that the feature will be included in a future firmware update, but that they'll fix the User Guide for now.
I liked that all Port Forwarding entries are both editable and able to be disabled and left programmed, something I wish were standard on all routers. I also checked for and found that loopback is supported for servers on forwarded ports.
The router also supports putting one computer in DMZ via a setting on the Security tab of the interface.
On the negative side, port forwardings are not schedulable by day and time, and - although I don't really think it's a negative - UPnP is not supported.
Turning to the Filtering (Access Control) features shown in Figure 6, I found the interface somewhat confusing.
Figure 6: Filters screen
It wasn't obvious, at least to me, that the Internet Access Policy and Filtered Internet Port Ranges were entirely separate functions. The Access Policy is schedulable by day and time, and up to 10 different policies can be created. Each policy has its own schedule and group(s) of LAN computers that it applies to, but is an all-or-nothing proposition. The Access Policy either grants all or denies all Internet access, and can't be limited to specific ports.
Specific port filtering is controlled by the Filtered Internet Port Ranges settings, but these settings can't be scheduled and apply to all LAN machines.
It's worth noting that Linksys hasn't yet provided even simple keyword content filters even though many of its competitors have had them for awhile. They do plan to implement the Web Filters features described in the User Manual in a future firmware release, but for now, you'll have to do without the ability to block Web Proxies, ActiveX, Java, and Cookies.