The crux of ISDN: what it does for your business - integrated services data networks - ISDN Forum - Column

Communications News, May, 1992 by Kevin Tanzillo

The focus of ISDN has clearly

< shifted from the technology to its

applications, and that might be the best thing that could happen to it. At the recent Wave conference, Bell

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Atlantic showcased an ISDN-based disaster recovery scenario, yet never really used the term ISDN. At least one other operating company took the same approach at a service rollout last fall. This makes sense for two reasons.

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First, the agonizingly slow advancement of ISDN has given it a bad rap. Just listen to the snickers of the cynics when ISDN is mentioned at some trade show seminars. Second, the telcos will eventually

< target much of their marketing efforts at smaller, less technologically savvy, users. These people haven't the slightest idea what ISDN is and don't really care. All they want to know is "what will it do for me?" If your company sets up an ISDN-based < work-at-home program, for instance, the people involved will think it's neat that they can talk on the phone at the same time that their PC is tied to the office network via the same line. But if you start explaining to them that it's because of ISDN and these two B channels and... well, watch their eyes glaze over. The focus was also on applications at

< the latest meeting of the North American ISDN Users Forum. Seven of them were profiled, including a primary rate LAN bridging application that could prove cost-effective for data use.

    Ethernet LAN bridging.



 This uses
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bridge routers working with NeXt and Sun workstations to transfer large files of E-mail and attached voice mail information across the network. It uses switched primary rate ISDN rather than dedicated T1. An Ethernet controller can provide seamless recovery in the event of failure as well as additional bandwidth during peak periods.

    Digital Realty.



 This allows real estate
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agents to retrieve images of particular homes and display them on in-office workstations. The images would be stored in databases maintained by realty boards' Multiple Listing Services. This produces savings because potential buyers can narrow their choice before they go out riding with the agent to look at homes.

    Distance learning.



 Users of Macintoshes
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and PCs at remote sites can access computer-based training via 9.6 kb/s X.25 D-channel packet-switched data.

    Remote interactive laserdisc access.



 This brings still and moving images and
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sound to a workstation. Full-motion compressed video is transferred over an ISDN basic rate 128 kb/s line. This has lots of potential for training in the health care industry.

    Intrusion detection.



Using terminal
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adapters, video equipment and access control relays, security personnel can use a single B channel to watch four sites on one screen via still images that are refreshed every half-second. In the event of a security breach, the surveillance center can change to a full-screen view of the affected site, using the second B channel for voice communications.

    Emergency dispatch.



 This is essentially
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a switch-to-host application using automatic number identification. As a call comes in, emergency personnel receive a screenful of data to indicate the source of the call and relevant information about that site.

    Extension of ISDN.



 This involves
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transmission extenders and other equipment to move basic rate ISDN beyond the normal loop. The signal can be transported via T1 and extended to a specific site. In this case, ISDN was extended from Huntsville, Ala.'s University central office with T1 to the Main and Toll central office and then to the Von Braun Civic Center, site of the ISDN users' forum gathering. Several of these applications were

< developed or are being refined at Redstone Arsenal in Huntsville. The Army base is doing some superb work with ISDN and is also the site of BellSouth's ISDN laboratory.

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