Get the most from fractional T1: sky's the limit in bandwidth options up to DS-1

GET THE MOST FROM FRACTIONAL T1

The need to tailor communications services to specific customer requirements is a driving force in today's private-line marketplace--right alongside customer demands for hands-on control of their private-network resources.

The provision of sub-rate services ranging from 2.4 to 56 kb/s represented a start.

Now, with the advent of the latest fractional T1 (FT1) services, the way is open to provide customers nearly unlimited bandwidth options up to the DS-1 rate.

Soon, FT1 services will be combined with other capabilities to deliver network monitoring, time-of-day scheduling, and customer-controlled reconfiguration. It will provide bandwidth on demand for meeting peak-load or other short-term requirements.

FT1 services, such as our pioneering Intelliflex, uses a software-controlled digital cross-connect switch (DCS) to subdivide or 'open' a full DS-1 circuit into 24 DS-0 (64-kb/s) channels.

Customers can opt for any number of DS-0 channels for point-to-point transmission of voice, video, or data.

New 64-kb/s offerings permit customers to use the entire bandwidth of the 64-kb/s channel. This will help multinationals requiring linkage bandwidth in 64-kb/s increments, and is ideal for bundled and nonstandard bandwidth applications such as videoconferencing.

FT1 delivers a compelling set of advantages to customers who need the quality, security, and performance of fiber-optic communications but whose applicatins can't cost-justify the use of a full T1 link.

FT1 lets you map bandwidth to specific needs, paying only for what you use, sometimes at huge savings over alternatives.

Only What You Need

If you run a 19.2-kb/s network with 14 nodes--five FT1 channels cost a fifth of a DS-1 circuit. You can buy 384 kb/s as a back-up link for critical data-center operations, or 768 kb/s for videoconferencing (respectively a quarter and a half of full DS-1). Even a single DS-0 carrying a data at 56 kb/s usually costs a lot less than a typical carrier's sub-rate 56-kb/s data-channel offering--including our own.

Another major advantage of FT1 is the ability it offers for fast, easy expansion of bandwidth to meet growth needs following initial installation of service. Five-day turn-up of additional DS-0 channels is a lead time that will shrink.

This capability relieves customers of much of the planning lead time otherwise necessary to cost-effectively grow bandwidth capacity, and allows a near-immediate response to unanticipated expansion requirements.

The technical requirements for implementing basic FT1 service include:

* Local access. The local loop to FT1 services generally will be at the DS-1 rate. DCS equipment won't accept transmissions below that.

* Framing and timing. The framing requirement is for D4 Superframe. Customer-provided equipment must be able to accept DCS timing at the DS-1 level. Most DS-1 muxes now in use meet these requirements or can be upgraded by the manufacturer.

Once local access is accomplished, the customer organization basically has complete ownership of its FT1 resources, with the ability of dynamically reassign applications among available DS-0 channels using its own software-controlled DS-1 muxes.

With software-controlled mux s, FT1 DS-0 channels can be ued in any combinaton to transport voice or data at different times of the business day or night, under the customer's direct control.

Basic FT1 service is generally cost-justified for two to three 56-kb/s data channels, or three to four 9.6-kb/s data circuits, or seven to eight voice or analog data channels.

Another important customer requirement--and one that goes beyond the capabilities of basic FT1 services--is the growing demand for use of the full 64 kb/s inherent in a DS-0 channel.

Both traditional 56-kb/s sub-rate and basic FT1 DS-0 offerings are limited to 56 kb/s of useable tranmission capacity, by virtue of the need to reserve bits to meet line-coding public-network needs.

But technological advancements have overcome this limitation, delivering a full 64 kb/s to meet a variety of application requirements inadequately met by 56 kb/s.

COPYRIGHT 1990 Nelson Publishing
COPYRIGHT 2004 Gale Group