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There are two central issues you must resolve before you look at remote-access servers: How many users will the server need to support, and what will users need to work remotely. The answers have a direct impact on determining the port density you need now and the feature sets you'll require later.

More Is Better, Sometimes Because SOHO remote-access servers generally come with a fixed number of ports--usually between two and eight--it's important to choose one that will serve your existing user base. It also is important for the server to offer some expandability or you'll quickly end up with port saturation and annoyed users.

One of the first aspects your users will notice about a remote-access installation is line availability and, after getting a busy signal, the amount of time it takes to get a ring. Port ratios and usage times work together to tie up ports. There's no hard rule in determining a user-to-port ratio. Typical installations range be tween 8:1 and go as high as 20:1. Bear in mind that the greater the ratio, the more likely your users will be greeted with a busy signal. A higher port density will reduce the likelihood of getting a busy signal but also will leave lines sitting idle. The user-to-port ratio illustrates only part of the usage picture; determining how long, on average, each user will be online will affect line availability.

For example, assuming all of your users wish to make a remote connection in a given hour and they normally stay online for 20 minutes, 25 percent won't be able to connect at all given a 4:1 user-to-port ratio. Furthermore, the chances of connecting drop quickly as more users contend for the ports. On the other hand, if your users stay online for an average of 10 minutes, you'll be able to provide service to more users with fewer ports.

Generally speaking, if your users connect primarily to send and receive e-mail, providing they read and write e-mail offline using say, QUALCOMM Corp.'s Eudora Pro or Microsoft Corp.'s Exchange, they'll only be on long enough to complete the mail transactions--approximately five to 10 minutes. If they're using network services or transferring larger files such as documents or spreadsheets in addition to e-mail, online times of 20 minutes and longer aren't unusual.

The price per port can range from $162 to $1,000, and those prices can be deceiving on the surface, since not all servers ship with modems. If the server doesn't ship with modems, you can estimate price per port by multiplying $150 (for a V.34 modem) by the number of ports. Buying third-party modems means you can use modems you feel work best instead of being locked into a specific brand. If the vendor doesn't provide installed modems, ask for an approved modem list. If the vendor doesn't have such a list, be sure you have the time and resources to invest in troubleshooting communications problems if a specific modem and remote-access server don't work well together--otherwise a turnkey solution might be bet ter-suited to your needs. If you go with a turnkey solution, be sure to ask who makes the modems and if the modem firmware is upgradable. Firmware updates let vendors add features such as increased performance and reliability without having to buy new modems.

No Two Servers Are Alike There's quite a gap between the feature sets offered in remote-access servers and the prices for each server. It's important to note that higher prices don't necessarily add up to more features. At the very least, the server you choose should let users connect as a remote node to your LAN.