You're unlikely to find high-powered technical support in the branches, either. Even if the enterprise is blessed with a network design staff and a central helpdesk, you've got the "E.T., phone home" problem. You may need to rely on local data-entry workers to open the shipping boxes and make a router work before they can tap in to communicate with the gurus in the home office. Manufacturers are working hard to serve this market. Some have introduced significant upgrades in recent months; others will roll out better user interfaces by the end of the year.

We tested 10 devices that connect small or branch offices via Basic Rate ISDN to the Internet or corporate intranet, divided into two categories. 3Com Corp.'s OfficeConnect ISDN LAN Modem and Eicon Technology Corp.'s Diva LAN ISDN Modem had the best grades among the LAN modems, which are targeted to remote branch offices that have fewer than 25 workstations on a simple LAN, with a dial-up BRI ISDN connection to the outside world. Some workers need occasional access to the Internet, while others may connect to the corporate intranet. In this LAN modem category, we assume that low purchase and use costs ($500 to $600 list; everybody shares a single IP number dynamically assigned by the service provider) are more important than fortress-level security. Password authentication plus the inherent masking of NAT (network address translation) is adequate. We placed FlowPoint Corp.'s 128 ISDN Router, Ramp Networks' WebRamp 410i and Adtran's Express 4120 in this category as well.

If you're willing to pay closer to $1,000, you can choose richer-function devices that also can support routing information tables, firewalls and VPNs (virtual private networks). Motorola's Vanguard 80 won our Editor's Choice in this group, which also includes Cisco Systems' 804 Router, Netopia's R3100-UP and Lucent Technologies' Pipeline 85, as well as OpenRoute Networks' GTX 1000, a model shipped by OpenRoute to meet our requirement for two analog telephony ports. We found the GTX 1000, with its modular WAN interfaces, to be overqualified in this field. It's a much better product than you might infer from its grades in our report card.

We weighted our LAN modem assessments to reward the devices that would be easiest to configure and manage. They provide the best value for small offices that operate out at the end of an ISDN circuit, with limited technical help at their disposal. The top grades went to those products that right out of the box require you only to plug in the cables, boot up a DHCP-set workstation, and type something like "lanmodem" or "fast.start" in the browser's URL window to get started.

For the configuration/management category in both report cards, we give highest marks to any device that can be fully handled with a browser or well-designed Windows interface. We reduced the grade for any product that makes you resort to a telnet or console window to complete or fine-tune an installation; we docked it further if it makes you call in technical help to guide you through the command-line interface.

We adjusted router category scores to account for the devices' higher prices. The scores reward devices that have higher capacity and better functionality. Motorola's Vanguard 80 offers clear configuration options and sophisticated router features, and we like it a lot. But look closely at Cisco's 804 router if you want to integrate your branch-office router with other servers and routers in an all-Cisco enterprise network, and Lucent's Pipeline 85 if you want to support dial-in telecommuters as well as outgoing LAN users.

All the devices we tested came with U-interfaces, eliminating the need for an intermediate NT-1 ISDN termination box. On the LAN side, FlowPoint's FP128 and Motorola's Vanguard 80 have only one port that connects to one or more hubs that you supply. With one exception, all the others have four jacks for connecting PC workstations directly or through a 10BASE-T hub to the router. (Netopia's R3100-UP has eight jacks.)

Most purchasers of branch-office ISDN routers still need support for analog telephone(s) or fax. We included this in our requirements; all participants provided units with two RJ-11 analog ports for connecting POTS handsets or fax machines that can be configured to dial out or receive voice calls on the ISDN B channels. And they all worked. We rigged a setup that let us play a test tape through each system and listen to the result. We also picked up handsets on each line and found that call bumping (pre-empting data traffic on a B channel for an outgoing voice call) worked as expected.

If you have provisioned your ISDN B channels for voice and data, most of these routers offer "data over voice," which can save money wherever per-minute channel use charges remain higher for carrying data than they are for voice. Activating this feature will label data traffic as voice.