The first bandwidth speed test interoperability test report was issued about a year ago. The report includes information on the products tested, an interoperability matrix, and the test configuration details.

Decision Time The key to judging whether you need inverse multiplexing as part of your WAN mix lies in the topology of your enterprise, the types of applications you are running, the volume of traffic you need to move between sites, and the consistency with which your WAN circuits are in use. For most organizations, it will be a mix of technologies. Inverse multiplexing will probably not satisfy all WAN requirements for all organizations. In most cases, a combination of dedicated backbone and bandwidth on demand will be the right approach.

Talk to any telecommunications executive at a larger bank, brokerage house, or insurance firm about their network, and odds are the phrase T-1 will eventually creep into the conversation. Large bandwidth digital transmission services such as T-1, T-3, and fractional T-1 are transforming the networks that support the financial industry, providing the means to deliver the next generation of technology at relatively low cost. The viability of T-1 has been growing, notes a senior consultant in the corporate networking unit of Arthur D. Little & Co., Cambridge, Mass. These types of services, he says, have been widely accepted in the financial world because they offer cost reduction and increased reliability and flexibility in private networks.

Naturally, lower cost is what made T-1 attractive initially. Around 1984 or 1985, the tariffs for T-11 relaly began dropping and there was a realization that some T-1 circuits could be used as voice channels. So for the price of nine or 10 analog voice lines, or five or six 64 kilobit per second Kbps data lines, you could get 24 full 64Kbps channels. Five years later, the allure of leasing 1.544 megabits per second (Mbps) of bandwidth with a T-1 or even 44.6Mbps for a T-3 trunk at what amounts to a bargain rate has not diminished, especially since that discount fare continues to drop.

When AT&T first introduced its Terrestrial Digital Service in June 1983, the monthly rate for a T-1 circuit between Chicago and New York was $ 27,000 a month. Since that time, the monthly tab for such service, now called AC-CUNET T1.5, has dropped steadily. It now stands at $ 7,200, or less than one-third of the initial cost.

Some of those costs, however, have been shifted to other areas. Ninety-five percent of the cost reductions for both switched and private line services have been driven by FCC decisions. The main reasons for price decreases are not the use of the state of the art technology or reductions in manpower, but the fact that costs that were previously assigned to these services are now assigned at the local level, in the form of access charges levied by the Federal Communications Commission and local exchange carriers.