The DI-604 is the classic case of "Big things come in small packages." But dont let the 604s diminutive stature fool you. Inside this little $45 box lurk admin features-o-plenty, and the price is right. In fact, the DI-764 has the same administrative features found in its big and far more expensive brother, the DI-764. The main difference between the two is that the DI-764 has 802.11a and b wireless networking support.
We could spend a lot of words telling you what we liked about the DI-604 but basically, we liked the same features in it that we liked in the DI-764. The 604s compact size allows it to be tucked away easily with your cable modem or DSL modem, and weve been running one of these 24/7 in our lab on our T1 line for about two months now, and it has been very solid, serving up IP addresses, and never crashing.
Our findings during Unreal Tournament testing were also the same as those seen with the DI-764. Getting an advertised server to be visible on the UT Master Server list required enabling either port forwarding (which D-Link calls "Virtual Server") or port trigger, which D-Link calls Special Applications. Ditto for results using Nmap, but just to recap:
We scanned the DI-604 using Nmap, and looked at the port addresses used by Unreal Tournament. On TCP, Nmap reported these ports as being filtered, whereas on UDP, it reported them being open.
Nmaps method of determining whether a given UDP port is open however seems a bit suspect to us. It sends 0 byte UDP packets to the specified port of the target machine. If Nmap receives an "ICMP port unreachable," the port is assumed to be closed. However, if no response is received, Nmap assumes the port to be open. As it turns out, the routers we tested here are ignoring the port scan and discarding the probe packets, meaning that the ports are not open, and therefore do not pose a security risk. This was confirmed with the vendors, a look at the router logs, and by doing additional scans using Gibson Research test tools.
Next, we tried to see a shared folder on a Windows machine that was behind the routers firewall. Windows file sharing uses ports 139 and 445, and TCP port scans of both of these ports showed them to be filtered. We were unable to see either the machine itself, or the shared folder on the target machine.
About the only complaint we have about the DI-604 is that it only has four ports on its 10/100 LAN switch. An eight-port version of this (maybe called the DI-608) would be a nice addition to the D-Link lineup. D-Link currently offers a seven-port broadband router called the DI-707, which appears to come close, and its street price is around $90. But this minor quibble aside, the DI-604 is a solid offering from D-Link, and brings a lot to the table for the money. If your network is small, the DI-604 will make for a reliable nerve center to keep the whole thing humming.
Just like the DI-764, setting up the DI-604 was very straightforward, and the Web-based admin interface has an initial setup wizard that allows you to configure the most vital settings to get you up and running. Like the 764, we also had the DI-604 configured and ready to roll in about five minutes.