A Brief History of Telebit

High Speed Modems

Telebit was originally founded by Paul Baran, the inventor of packet switching, to make high-speed modems. At the time, the competing products had a maximum transfer rate of 2400 bps, but Telebit used multicarrier modulation with a patented Packet Ensemble Protocol (PEP) to achieve more than 9600 bps on a normal telephone line. This resulted in Telebit's first (and perhaps most famous) product, the TrailBlazer modem.

By using multicarrier modulation and PEP, the TrailBlazer could maintain high-speed connections even on poor quality phone lines that wouldn't work for normal modems. This was particularly useful on international calls.

The TrailBlazer was particularly well received by the UUCP community, because it spoofed the UUCP "g" protocol for high throughput.

The T1000 was a cost-reduced model that was limited to a maximum of 9600 bps. The T2000 was a version of the TrailBlazer supporting synchronous links.

Internet Routers

Telebit developed the world's first dial-on-demand Internet router, the NetBlazer. The NetBlazer supported Ethernet as well as SLIP and PPP link protocols over modem links. With the addition of a synchronous interface card, the NetBlazer could also be used with 56K and T1 leased lines. Later support was added for ISDN basic rate interfaces (BRI).

Initially the NetBlazer only supported IP routing, but support for IPX (Novell) and AppleTalk protocols was added in the version 2 software.

Many NetBlazer models were based on PC platforms, although the NetBlazer PN family used a custom 386-based logic board in a modem case, and the NetBlazer LS family used a Motorola MC68EN360 processor in a modem case.

Even Higher Speed Modems

When the V.32 standard (9600 bps) was published, Telebit offered the T1500, which was a Trailblazer with a Rockwell V.32 data pump module added. This was later superceded by the T1600, which used Telebit's own implementation of V.32.

The T3000 modem added V.32bis support (14400 bps), and the WorldBlazer added fax support.

However, Telebit was somewhat taken by surprise by V.34 (28800 bps), and did not have a product in development soon enough to satisfy the market demand. Instead, the company executives looked for a company with V.34 technology that could be acquired.

The End

In 1994, Telebit Corporation merged with Octocom Systems, a small, little-known modem company in Chelmsford, Massachusetts. The board of directors decided to have Octocom's management run the combined company. All manufacturing shifted to Chelmsford for a supposed reduction in burden rate that never actually materialized. In fact, aside from the actual manufacturing costs in Chelmsford being higher than in California, the company stopped paying one of its large semiconductor suppliers in a timely manner, and that vendor dropped Telebit's account and required Telebit to start buying chips through distributors, which pushed the costs up even higher.

Management claimed that the company would keep the west coast office open for NetBlazer engineering. However, as soon as the VP of Engineering resigned (spring 1994), the company announced that the west coast office would be closed.

On October 25, 1996, Telebit Corporation was acquired by Cisco Systems, Inc., although they sold part of it back to the Telebit Corporation executive staff to form a new privately held corporation named Telebit Incorporated.

On August 11, 1997 Telebit Incorporated merged with ITK Telekommunikation AG, forming ITK International, Inc.

On July 1, 1998, Digi International announced that it had signed a definitive agreement to purchase ITK International, Inc.

Digi International had no interest in the Telebit products, and has discontinued them.

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Last updated November 15, 2003

Copyright 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 Eric Smith


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