posted by David Adams on Fri 26th Jun 1998 11:41 UTC, submitted by John Renyolds
IconHaving determined at the time we began the experiment that ISDN was the only viable form of high speed internet access available in our area, we set out to get wired with ISDN.

Having determined at the time we began the experiment that ISDN was the only viable form of high speed internet access available in our area, we set out to get wired with ISDN.

We tested three terminal adapters of different types, using three types of computers: A Windows 95 box, a Mac laptop, and a Linux box. We tried single channel ISDN and bonding. We wrestled and wrangled with our phone company to get the line installed correctly, and we shopped around for the best price.


A visit to the USWest web site eventually produced the rates for ISDN service, which were a little shocking. US West charges $80 for installation of an ISDN line (which can be used for two analog phone connections) and $70 per month for unlimited access. They have metered service starting at $40 per month, but we calculated that we would easily go over the $70 mark, especially since bonding two channels results in connection fees (by the minute) on both channels. We wanted the full 128k bonded service, so we bit the bullet and prepared to shell out $70 plus taxes and assorted fees per minute.


We were lucky. We found out that although ISDN service is widespread, there is a line length limit from the switching station which creates holes even in urban areas that ISDN can not reach until the phone company updates its infrastructure. Additionally, an OS News staffer in the Washington DC area who performed tests for this article concurrently, was pleased to discover that Bell Atlantic's rates were much lower, but that he could not get ISDN to his house because of some obsolete wiring. It took Bell Atlantic six months to finally install his ISDN.

It took US West two days to install our ISDN. However, it wasn't just plug-it-in-and-go. Our adventure was just beginning.

In order for any ISDN terminal adaptor to work, it must be configured to communicate with the phone company's switches. You must also set your identification numbers, known as SPIDs. Unfortunately, US West told us the wrong SPIDs, so we called them and got them to fix that problem for us within a few days.

An ISDN-ready ISP

Once we got all the numbers we needed, we were ready to get online. We had shopped around of an ISP to over our dial-up access and discovered that prices varied wildly. Some ISPs charge outrageous set up fees, as much as $50-$100. For dual channel ISDN, monthly fees ranged from thirty dollars to well over $100. The ISP we settled on, XMission in Salt Lake City, was among the lowest we found, and has a reputation for the fastest access in the area.

Getting the ISDN to work was then a matter of carefully reading the instructions and trying to configure each terminal adaptor (TA). In each case, this involved connecting via a serial port and entering in numbers via some kind of interface. We'll cover the differences in the hardware in the next section, but none of the TAs we used was any easier than any other. It an hour or so, we were ready to make the call.

The Hardware

We used three terminal adaptors for our test, representing the full spectrum of available ISDN equipment:

An el-cheapo refurbished Motorola BitSurfr Pro that cost about $150. It's a basic terminal adaptor that plugs into the serial port like any modem. By swapping the cable and downloading drivers off the web site, we were able to get it working with the Wintel box and the Mac. Performance was passable. The biggest performance bottleneck was the serial port. Both the routers were much faster, with higher throughput and better latency. In order to dial up with this TA, we use the standard PPP dial-up software just like for a modem. However, it dials up a lot faster.

Second, we tried a Xyxel Prestige 100U ISDN router. A low cost router that supports two channels, has one ethernet port and two analog phone ports. It supports IP and DHCP. Performance was excellent, and this router has all of the features that we needed, though many people may need routers that support other protocols or have ethernet hubs built in. This router cost about $500. In the case of both of the routers, they dial up on demand, requiring nothing more than entering a URL into the browser. They connect in a matter of seconds.

The other router we tried was the cream of the crop: The Netopia ISDN router. It supports IP, IPX, and Appletalk, has both ethernet and localtalk network ports, and both PC and Mac serial ports. It has built in PC card slots for insertion of a modem for remote configuration and a built in web server for direct configuration via a web browser. It was packed with features both for increased compatibility and ease of use. But you pay. It costs about $950.

Hardware Comparison

With the speed advantage of using ethernet rather than a serial port, both of the routers were much faster than the Motorola terminal adaptor. Plus, as we had several computers in the house, a plain old TA was out of the question. We hooked up the router to our small LAN (with a Win95 box, a Mac Powerbook and a Linux box on it) and we could all use the ISDN at once. There were no noticeable speed differences when we were all on at once unless someone was doing a download. In fact, the routers were set to only connect to the second channel if it was needed. For web browsing, we only needed one. We used DHCP, so when we logged on the router would automatically assign us an IP address.

We did find one advantage with the Motorola TA. One resident of the house wanted ISDN primarily to play Age Of Empires (a very fun strategy game) on the internet. With the routers, since it simulated IP addresses for the individual machines, he could not connect with other AoE players. After some investigation, we called our ISP and requested a subnet and five IP addresses. After reconfiguring the router with the subnet and IP addresses, we could play Age of Empires. We even gave the Linux box a static IP address so we could use it as a proper server. I used Timbuktu to access files on my powerbook from work (accessing it via a static IP address). The subnet and IP addresses cost us an extra $20 per month because we had to upgrade to a business account, but it was worth it.

Since we were sold on the speed and features of a router, which of the two did we like best? As the Mac user, I liked all the Apple-friendly features of the Netopia, but I didn't need them. I also didn't need IPX. The friendly web-based interface was actually not as useful as the plain text interface that we accessed via serial port and terminal emulator. The Xyxel router also dialed up in about two seconds, while the netopia usually took five or six. Add that to the lower price, and the Xyxel is a no-brainer. However, our decision was based primarily on the fact that we did not need the fancy features.


About a month after getting set up our ISDN stopped working. We called our ISP and they told us that they had just upgraded their ISDN hardware on their end and that it might be a problem with our router. They offered to sell us a 3com router that they were sure would work. ISDN is supposedly tried-and-true technology, but it seems that most ISPs have little grasp on it. We eventually found out that when we had originally called US West about our bad SPIDs, somebody turned in a work order which had finally been done, and they had changed our SPIDs back to the old ones without telling us. We were down for over a week because of this confusion. The Telecos are worse than the ISPs. With our experience with both USWest and Bell Atlantic, you'd think ISDN was invented yesterday.


For us at least, ISDN is a pretty expensive operation. At an average $80 bill from the phone company and $50 from our ISP, that's a lot to spend on internet access, even for three people. But now there are three people who will never ever go back to modems. No matter how much it costs, I will never go back to anything slower than ISDN. We noticed that with normal web browsing we only used one channel. That means that 64k of bandwidth is fine unless you're downloading a large file. It's the latency, stupid. The moral of this story is, who cares if they're offering 64kbps, 1.5mbps, 3mbps, or 300mbps. Only if the latency is comparable to ISDN is it going to feel that much faster.


A few months after we got set up, US West announced ADSL at $40 per month. At 1.5mbps and comparable latency, mixed with a lower cost and discounts on installation, it looks like that's where we're going. But they don't support routers, so only one computer at a time can be connected to the net. In order to get around that we'd have to dedicate one machine to act as a gateway, using one of several (commercial or free) software-based IP gateway packages. That will be a whole new adventure.

In part three of our three part series, we'll cover the high speed internet access technologies of the future. Some, like DSL, are already availabel to some people. Some are still a pipe dream. How will we all be connecting to the net in ten years? Time will tell.

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