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Aspects of Integrity in the NII

John C. McDonald
MBX Inc.

The national information infrastructure (NII) has a variety of definitions and gives rise to various perceptions. One such perception is that the NII is a rapidly expanding network of networks that, in totality, achieves the national objectives set forth by Congress and the Clinton administration. No matter what the definition, this telecommunications infrastructure is a key element of the expanding information revolution that we are currently experiencing. Plans are being made by many sectors of the economy to further use the resources of the NII to improve productivity, reduce cost, and maintain a competitive edge in the world economy. Included among the sectors with growing reliance on the NII are health care, education, manufacturing, financial services, entertainment, and government.

With society's increasing reliance on the NII, there is a corresponding need to consider its integrity. Integrity is defined as "the ability of a telecommunications infrastructure to deliver high quality, continuous service while gracefully absorbing, with little or no user impact, failures of or instrusions into the hardware or software of infrastructure elements 1."

Integrity is an umbrella term that includes other important telecommunications infrastructure requirements such as quality, reliability, and survivability.

This paper discusses various dimensions of integrity in the NII. Threats to integrity are presented and lessons learned during the past decade summarized, as are efforts currently under way to improve network robustness. Finally, this paper concludes that architects and designers of the NII must take issues of integrity seriously. Integrity must be considered from the foundation up; it cannot be regarded as a Band-Aid.

Threats to NII Integrity

Network elements can fail for any number of reasons, including architectural defects, design defects, inadequate maintenance procedures, or procedural error. They can fail due to acts of God (lightning, hurricane, earthquake, flood), accidents (backhoe, auto crashes, railroad derailment, power failure, fire), or sabotage (hackers, disgruntled employees, foreign powers). Architects and designers of the NII should weigh each of these threats and perform cost-benefit studies that include societal costs of failure as well as first-time network costs. Users of the NII should understand that failures will occur and should have contingency plans.

Over the past 10 years, public networks in the United States have experienced failures resulting from most of the threats described above. In May 1988, a fire in the Hinsdale, Illinois, central office disrupted telecommunications services for 35,000 residential telephones, 37,000 trunks, 13,500 special circuits, 118,000 long-distance fiber optic circuits, and 50 percent of the cellular telephones in Chicago 2. Full service was not restored for 28 days. The failure affected air traffic control, hospitals, businesses, and virtually all economic sectors. Two months later, technicians in Framingham, Massachusetts, accidentally blew two 600A fuses in the Union Street central office. The local switch stopped operation, and calls from 35,000 residential and business customers were denied for most of the day 3.

In November 1988, much of the long-distance service along the East Coast was disrupted when a construction crew accidentally severed a major fiber optic cable in New Jersey; 3,500,000 call attempts were