An Experience Review

On Friday November 14th, everything came together for my new ISDN (Integrated Services Digital Network) service. The final steps were installation of the inside line (I changed rooms for my computer setup) and setup of the AdTran Express XRT terminal adapter. My ISDN service that I had ordered from Bell Atlantic a month earlier was finally live!

Why ISDN?

For a number of months I had been looking into alternatives to increase the speed of my internet activities as I spent more and more time maintaining and updating Macs Only! plus other online activities. Earlier I had traded in my Zoom 28.8K modem for a 56K model in search of greater speed. I did this because my ISP promised 56K-Flex service beginning in August and Zoom would switch modems for only $79. My Zoom 28.8K upgraded to 33.6K only connected at 26.4K to 31.2K but mostly at 28.8 K despite my ISP and several others that I tried advertising 33.6K connections. The Zoom 56K Flex usually connected at 31.2K and the throughput was better than the 28.8K version. This rate continued even after my ISP installed and advertised 56K Flex service in late August.

The alternatives to "56K" service are cable, ADSL (Asymmetric Digital Subscriber Line) and IDSN. Unfortunately, ISDN turned out to be my only alternative. My cable company won't offer internet service until next summer. Bell Atlantic's experimental ADSL service is not offered at my local telco switch. This was particularly disappointing because the speed is over ten times that of ISDN and the ADSL cost is only $30 per month plus the ISP cost--no installation or wiring charges and no charge for the "modem". Bell Atlantic plans to offer ADSL more widely next summer.

Fortunately, Bell Atlantic offered a special deal on ISDN as well--no hookup charges, a steep discount on the terminal adapter, flat rate ISDN charges ($60/month at my usage rate) and ISDN 128K ISP service for $21.95, less than the $30 charged by my ISP for a year's payment.

Ordering ISDN

Before ordering ISDN, I read Steve Tannehill's ISDN experience and "ISDN for Dummies"--I've found that the "Dummies" line of paperback books are very informative and the one on ISDN is no exception. These sources at least allowed me to be conversant with the various aspects of ISDN which I had feared to be too arcane to grasp. Not so today. It's been simplified a lot. Ordering ISDN from Bell Atlantic turned out to be easy but the reading really helped me understand what I was being asked--it was a good time investment.

I called Bell Atlantic's Infospeed and a sales agent walked me through what he needed to know. The biggest decision was the terminal adapter. ISDN service has two 64K channels, each with its own telephone number. The two channels can be used in tandem to get 128Kbps and effectively 230.4Kbps with compression. I traded a second one-number analog line for the digital ISDN line, meaning the net cost was less than $40 per month, so the second biggest decision was picking the two new ISDN telephone numbers. Fortunately, out of the list of 10 numbers there were two that were the same except for the last two digits. The Bell Atlantic sales rep arranged for the outside line connection, the inside line work (only needed because I didn't have telephone service in the new computer room), and the terminal adapter.

I had to switch ISP's to Bell Atlantic, easier I figured to fix any problems and it was cheaper. My ISP that I had used for two years wanted $30 per month for 128K service if paid a year in advance while Bell Atlantic charged only $21.95 per month, paid monthly and available throughout the region. I also had to buy a M-F 25DB RS-232 cable to connect up my 56K analog modem to the terminal adapter, an excellent feature that I'll dscribe in a moment. Finally, I had to be home for the inside line work.

The Terminal Adapter (TA) Choice

I had a choice of a terminal adapter (TA), it's like a modem, or a router. The router is like an ethernet hub that allows several computers to use ISDN service over the ISDN line at the same time. Routers also cost 3-5 times the cost of a TA. Each TA had two ports (POTS for Plain Old Telephone Service) for connectng and using up to two analog devices like a phone, fax or modem at the same time as the TA. This allows two computers to be online at the same time, one at ISDN 64K speed and the other up to analog's 56K speed as if it were connected to a regular telephone jack but with the noise-free quality of a digital line. This and cost mitigated against a router.

The TA choice was limited to two for the Mac out of seven that Bell Atlantic offered. I chose the AdTran Express XRT. In addition to the two POTS ports, the AdTran has an RS-232 port that allowed my 56K modem to work off the TA with a simple software control panel to select between them. I have several services that I need to reach with an analog modem so the ability to switch between the TA and analog modem without disconnecting and reconnecting the serial cable from the computer was the selling point. Fortunately, it was also the one available at a steep discount, just under $200. More on the TA in a moment.

The Setup

The inside line's installation was scheduled for the morning of Friday, November 14th. I received the TA by UPS on Tuesday, November 11th and the outside line was connected Wednesday, November 12th, killing my second analog line. If I didn't already have two analog lines, I would have been without telephone service for about 48hrs. The ISDN line man showed up Friday morning as scheduled and in less than an hour my computer room was wired with an ISDN connection and a connection for my first, now only, analog line. The extra inside wiring cost $100 but it was not a necessary part of the ISDN setup if I had not moved rooms. The wire for some TA's have an RJ-45 jack on the TA end and an RJ-11 (regular) jack on the other to plug into the telephone wall jack. If an RJ-45 wall jack is needed, it is not to difficult to install in place of the usual RJ-11, saving the $100.

The AdTran Express XRT TA comes with installation wizard (thinking about it, "wizard" is an appropriate name for arcane Windows installations) diskettes for Windows 95, 3.11 and NT plus a Mac diskette. The 80-page manual has one small paragraph on the Mac installation and 20 pages on the Windows installations, fair enough. There was also a loose one-page insert covering the Mac diskette. However, that is almost all that is needed. Just insert the diskette, click on the application, click the several buttons on the dialog boxes and enter the two telephone numbers--no sweat. Well, then I encountered the first problem--no modem scripts (.CCLs) for the Mac's Modem Control Panel were installed nor included on the Mac diskette. Fortunately, it was early Friday afternoon and a call to AdTran's technical support line provided me with the location where I downloaded the appropriate modem scripts.

The AdTran can be configured to make a V.120 (57,600 bps) connection, a single channel 64Kpbs or a dual channel 128Kpbs connection--the latter two can be configured to allow 115.2Kpbs or 230.4Kpbs with compression. The AdTran has a software control panel to choose among these configurations and a switch in the back to toggle between 115.2Kpbs and 230.4Kbps. There is a checkbox to select the analog modem or the AdTran. The control panel could be better designed to be much more efficient but it is a derivative of the more complex Windows software in keeping with the Windows 95 plug-and-play paradigm. The switch turns out to be a real pain. It is one of four tiny switches in a bank that need a paper clip or other such thing to trip and it is in the back where you can't easily get to it. The switch has to be "on" to configure the AdTran and to select the analog modem. It has to be "off" to get the 230.4Kpbs connection. So I've got to trip it twice to go between the maximum ISDN speed which I need and the analog modem and back again. I'm not sure how long the switch will last under these circumstances and it is a major design flaw of the otherwise terrific AdTran Express XRT terminal adapter.

The second flaw is that there is no power switch. That's right, it's on all the time. This makes sense in that the ISDN line running through it can be a regular phone or fax line that most people would want on all the time. However, to disconnect or reconnect the modem cable which might happen once in a while or when the PPP software returns an error and the terminal adapter needs to be reset, it has to be disconnected from the power source by pulling out the transformer's plug. Why not have a simple power switch?

The AdTran Express XRT sold originally for nearly $400 but with no simple 230.4Kpbs switch up front (or better, a software switch in the control panel) nor a power switch anywhere. Obviously, more competition is needed to bring these simple no-brainers to ISDN technology.

Using ISDN

ISDN is fast. Going from a 28.8-31.2K connection to 128K is like going from an old 9600 B modem to a 28.8K modem--it is that drammatic. Well, almost. Clicking "Connect" on OT/PPP silently results in a working connection in 6-7 seconds rather than 20-40 seconds or more with my analog modem. Moving from site to site is noticeably faster as is the dowloading of pages. However, site resolution and page download speeds depend heavily on the speed of the server, the connection demand and the congestion on the internet--ISDN takes you to the limits of these congestors. File downloads generally are much faster with ISDN. My 33.6K modem usually connected at 28.8K and downloaded files at 3.0-3.3Kbps according to Netscape. The range was from near zero to the high 3's. Using dual channel ISDN my file downloads have varied widely but are usually from 9 to 15Kbps centering around 12. Speeds as slow as with my analog modem have also been encountered.

Conclusions

Is ISDN worth it? The upfront cost was $199 for the terminal adapter. Since I moved my office, I would have had to pay the $100 for an inside line anyway. It would have cost me about $5 for an RJ-45 walljack that I would've installed myself. The monthly charges, assuming I don't blow over the 140-hour maximum, are a net $40 for the ISDN service ($60 minus $20 for the old analog line that ISDN replaced) and a net of about $7 for ISP sevice ($22 for Bell Atlantic ISDN minus $15 for my old "56K" ISP service) for the total of a $47 per month increase.

I enjoy the speed and it makes my web work much faster. ISDN is cost effective for me but everyone will have to decide for themselves if their time is worth it.

Setting up ISDN is no longer arcane, at least not when dealing with Bell Atlantic. The most difficult aspect was dealing with two line installations on two different days by two different parts of the Bell Atlantic organization and even that went smoothly and on schedule. Setting up the terminal adapter consisted of clicking through a configuration application and entering nothing but the two telephone numbers that comprise my ISDN service.

From what I read, terminal adapters have come a long way to be reasonably dodo friendly. However, they still have a way to go to catch up to a simple analog modem in ease of use. The AdTran Express XRT came with no modem scripts, a tiny switch in the back that has to be tripped to configure the TA or use the connected analog modem and tripped back again to get the fastest mode, and no power switch. Since Bell Atlantic has a steep discount on the AdTran, I expect that a newer model addressing some or all of these shortcomings is just around the corner.

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Copyright © 1997 by Bill Fox.
All rights reserved--no commercial use permitted without my expressed permission.

Of course . . . . . . and I am proud to be an Evangelista! . . .

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