There's one final factor to consider when choosing a multiport analog router: Know what your ISP and existing servers support, both in terms of the 56-Kbps technology they use and their method of aggregating bandwidth. It can be a catch-22: Most ISPs support either x2 or K56flex, but not both. It's up to each organization to decide which way it wants to go. Although V.90, the 56-Kbps standard, has been ratified, it's not yet widespread.

Most ISPs also lack support for MLPPP, so in order to connect through such a service provider, the router must support load-sharing. The four products we tested offer something for every setup.

Multi-Tech Systems ProxyServer MTPSR3-200
The $1,400 ProxyServer supports almost every configuration we threw at it. Thanks to its good performance and the flexibility to use MLPPP or load-balancing, it's easy to shape your own dial-up connectivity.

Installation was a breeze for all the devices. With ProxyServer 200, we were configured and dialing on demand to two locations in minutes. Using address translation, as we did with all the devices, we were able to get DHCP addresses for our client workstations and immediately begin browsing on the Web. The setup program itself is Windows-based over a serial connection, but we could have used the Web-enabled, over-the-wire configuration tool. However, had anything gone wrong in the process, the weak documentation would have been of little use.

Load-sharing and MLPPP are among the many configurations ProxyServer supports. We configured ProxyServer to dial into our Cisco AS5300 using both. If you are connecting to an ISP, you probably won't be able to use MLPPP. But if you are connecting to a server in a central office, MLPPP provides a clean method of bonding traffic.

Using NAT makes it difficult to access remote-office machines from the outside. ProxyServer overcomes this limitation by using port address translation to make a remote-office Web site visible to the rest of the world. We simply directed ProxyServer to send all requests to Port 80 to the private IP address of our Web server. Likewise, we could have set up an internal e-mail server and done the same for Port 25.

ProxyServer offers the best overall performance in both proprietary load-sharing and MLPPP modes. In addition, unlike its competitors, it has a third modem built in. We could find only two shortcomings when measuring the device against its peers. First, its single Ethernet port means you'll need a hub. Second, unlike the other three routers, ProxyServer can't be configured to pre-empt a data line automatically when a voice call is placed.

Even with these shortcomings, ProxyServer offers almost all the connectivity features you could ask of a multiport analog router, and delivers good performance and tremendous flexibility.

Ramp Networks WebRamp M3i Plus
Ramp Networks popularized the aggregation of analog lines, so it's no surprise that the $1,099 WebRamp M3i Plus is a decent performer that's easy to configure and hassle-free to use. Its biggest drawback is its IP-only support--an issue that's addressed in newer WebRamp models.

WebRamp M3i Plus has a quick setup routine. Like Multi-Tech's ProxyServer, it is Web-browser-configurable, and we used both our Windows95 PC and our PowerBook 3400 to configure and monitor it. Using this routine, we found it easy to see whether the analog ports were connected and what error messages, if any, there might have been.

WebRamp M3i Plus, like Netopia Router and 3Com OfficeConnect, has one advantage over ProxyServer: It supports nondedicated phone lines for WAN connections. By connecting both the data line and a phone to WebRamp, we could configure M3i to drop data calls in favor of voice calls. We chose to dedicate our primary data line to the WebRamp and make the secondary line pre-emptable, as most users would do. When we made a voice call, the network was dropped, killing any data transfers going over that connection.