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Network outages frustrate users and telcos.

Recent telecommunications events on the East and West Coasts suggest, as a nation, we may be depending too much on advanced network technology. Our increasing reliance on sophisticated switching and signaling systems, fiber optics, and other elements provided to telcos and IXCs may prove hazardous to a user's network health.

Over three years ago, Illinois Bell suffered through a devastating central office fire. Last year, AT&T had a serious network outage that lasted nine hours. Recently, both Bell Atlantic and Pacific Telesis survived several serious network outages, whic affected millions of subscribers:

* Bell Atlantic outages in Maryland, Virginia, West Virginia, and Washington, D.C., took out service for five million customers for nine hours.

* Another Bell Atlantic outage knocked out service in Pittsburgh for seven hours over two days.

* Pacific Bell outage in Los Angeles affected over three million subscribers for three hours.

* Another PacBell outage in San Francisco knocked out over two million lines for about five minutes.

These outages initially were thought to be malfunctions in equipment associated with network signal transfer points (STP), integral parts of common channel signaling (CCS) networks. These special networks manage transport network activities such as call setup, call monitoring, and various administrative functions. The protocol used in these CCS networks is Common Channel Signaling System No. 7 (CCS7), a key component in ISDN.

Here's what, in fact, happened: A software bug--three lines of STP routing code that had incorrect bit patters--generated trouble messages. These conditions generated error messages which were sent to other STPs. Network traffic was subsequently rerouted around the failed STP. This is how the network stays in business.

Unfortunately, in these cases, large numbers of error messages caused by the bug tied up the CCS network. As a result, the overall network could not handle normal traffic, and users ended up with no service.

Are we sitting here with a loaded gun to our heads?

Regardless what you hear from the telcos and IXCs, we have a potentially serious reliability problem in our national networks. As you know, both telco and IXC networks are increasingly managed by CCS networks. However, most local and long-distance CCS networks do not currently interconnect. That's going to change over the next few years.

While service quality should definitely improve by interconnecting CCS networks, it also means outages of the type described here could spread to long-distance networks, creating nationwide outages of massive proportions.

Do safeguards work?

Both telcos and long-distance carriers maintain their networks have safeguards to deal with these scenarios. Can we be totally certain they will work? If this is indeed the case, telecomm managers will need network contingency plans more than ever.

It wasn't too long ago "the network" was virtually indestructible. Or at least most of us never really knew when an outage occurred.

How many of you remember when you could literally "follow" a call passing through a step-by-step or crossbar CO or PBX, for that matter? These networks, while slow and primitive, were reliable and easily fixed. Problems could be spotted fairly quickly.

But here's the rub: An outage in one bank of equipment would not create a domino effect to other switches in the same building or across the country.

I'll bet many of you miss those days, too. But we have moved forward rapidly. Perhaps a bit too rapidly.

Let me state for the record that I am not complaining about advances like common channel signaling, SS7, ISDN and the many other elements that make up today's "network." My concern is that we may not be using these building blocks to create totally "failure-proof" national network infrastructures. If, perhaps, the goal is "failure-resistant" networks, rather than "failure-proof," we may be on a collision course with disaster.

FCC hearings

The Federal Communications Commission (FCC) has called for meetings with Bell Atlantic and Pacific Bell to determine what the FCC can do to prevent these events from recurring. Ironically, in the FCC's late July rulings, the commission ordered the RBOCs to step up the deployment of SS7 so, among other things, 800 service portability could be achieved. The goal is to have extensive SS7 deployment in about 18 months.

We certainly hope the cart will not be placed in the wrong position, relative to the horse!

The implications of an all-CCS/SS7 network are quite sobering. First of all, the network will be entirely software-driven. Next, remember what happens periodically today to computer networks accessed through the public telephone network.

Now envision this scenario: An organization bent on causing considerable damage (political or otherwise) to the U.S. hires some of America's top computer hackers. The mission is to penetrate the nation's CCS networks and install viruses, time bombs, or other harmful code. Force the U.S. to the brink of economic collapse by threatening to sabotage the nation's communications infrastructure.

Could this happen? Experience has shown that no matter how secure something is, someone ca break into it. If this is indeed the case, then today's recession will appear like the "days of milk and honey" by comparison.

Gloom and doom is not our purpose in this month's column. Rather, we want to suggest telecomm technology, no matter how advanced, has a darker side that cannot be overlooked.

But we should not cast stones without offering some ways to deal with this situation. One such individual is John C. McDonald, currently president of MBX, Inc., a communications consulting and research firm based in New Canaan, Conn. Formerly chief scientist with Contel Corp. (and currently a member of GTE/Contel's Board of Directors), McDonald headed a distinguished panel of industry leaders in the late 1980s that analyzed network's survivability from a national security perspective.

Results of that study can be found in a report, "Growing Vulnerability of the Public Switched Networks: Implications for National Security Emergency Preparedness." It is available through the National Academy Press, Washington, D.C.

As we progress into the 1990s, telecomm managers wil be held increasingly responsible for network performance. Just as certain federal statutes hold company officers criminally liable for loss of vital corporate data, we should not be surprised in this policy extends to telecomm administrators as well.

Are you ready to accept that responsibility, without a plan of action?

Naturally, you can create a contingency plan or update your existing one. But you must remember your first line of communications is your local dial tone. What does your telco have planned to protect dial tone? How quickly can you expect your service to be restored in a disaster that affects many customers? Where are you in that magical list of who-gets-recovered-first?

It's your responsibility to know these things. If not, in time you may be held liable for a network disaster--regardless of the cause--that results in lost data, lost customers, etc.

What we are saying is to get your protection mechanisms in place now. Not next week or next year ... it might be too late.
COPYRIGHT 1991 Nelson Publishing
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1991 Gale, Cengage Learning. All rights reserved.

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Title Annotation:Communications Management
Author:Kirvan, Paul
Publication:Communications News
Article Type:Column
Date:Oct 1, 1991
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