This final section will attempt to capture all the rest of the features that you're likely to find in NAT routers that don't really fit neatly into any of the previous headings.
This feature allows you to access the admin screens of your router from the WAN (Internet) side. Very handy if you travel frequently and need to adjust a setting on your router, or if you're responsible for keeping routers at customer sites up and running. Since this feature can potentially allow anyone to gain control of your network if it's not properly secured, you need to look for products that have ways to make it harder for anyone besides you to control the router.
At minimum, you should be able to restrict Remote Admin access to specific IP addresses or range of addresses. Better yet, but harder to find, is the ability to specify the port number that you use to access the Admin HTTP server. This means that someone would not only have to know your router's WAN IP address, but also the port number that you've assigned.
Finally, although they are hard to find, a router that supports secure HTTP (HTTPS) is an even better choice if you need to administrate a router remotely. Fortunately, Linksys seems to have added this capability to their popular WRT54G wireless routers.
This feature was made popular by SMC's original Barricade line of routers. It allows you to connect a printer to the router instead of a networked computer and offload the printer sharing tasks to it. This means that printing doesn't depend on a particular computer being up and running, and can also allow you to move your printer to a more centrally located spot.
But it's much more difficult to find routers with built-in print servers today. Instead this feature looks like it has moved to being more frequently included in Networked Storage (NAS) products.
When you do find routers with print servers, they're more likely to support USB instead of parallel-port printers. In addition, most router-embedded print servers don't have much memory (limiting the size of files that can be printed), may not handle printing from MacOS computers, and don't support bi-directional printer features.
But if you must have this feature, check out the Netgear FR114P, FWG114P or Trendnet TW100BRF114U.
Dynamic DNS (DDNS)
Most of us have Internet service that uses a dynamic IP address that changes on a periodic basis. This doesn't bother most Internet users, but is a problem if you need to connect back to your LAN from across the Internet. You'd need to do this if you were making a VPN connection back to your home office, for example, or trying to monitor a "nanny-cam" to check up on what's happening at home.
Fortunately, dynamic DNS services can come to the rescue. These services let you register a domain name and use a client running on one of your LAN computers that tells the service when your assigned IP addresss has changed. So when you want to "phone home", you just use your domain name, which the dynamic DNS service keeps pointed at the proper IP address.
Since the router is the actual device that holds the WAN IP address, it makes sense to run the dynamic DNS client there instead of on a LAN computer. Many routers now come with built-in dynamic DNS clients that support at least dyndns.org and more frequently services such as TZO.com.
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