Networking's greatest debates in LANS + WANS

Including IPv4 vs. IPv6, routing vs. switching, Packet switching vs. circuit switching, Ethernet vs. Token Ring, and Cisco vs. the rest,

Interest in their modems was sky high, but they didn't interoperate, so customers - particularly ISPs whose modem banks would have to support the technology in order for end users to reap its benefits - steered clear. No ISP wanted to bet on x2 or K56flex and wind up having to upgrade them later if it turned out they bet wrong.

The warring factions decided they were killing the market for the faster modems, and agreed to a common standard known as v.pcm. After that some 95 million of the modems were in service within two years.

It seemed like a simple solution, but all the issues weren't settled. Townshend still held five patents on the underlying technology and after protracted lawsuits, exacted royalties that at their peak amounted to US$2.50 per modem. That netted him enough money - do the math - to carry on defending the patent for years. As late as 2004, he was still settling with vendors who had been using his invention for years without paying royalties.

For all the trouble it caused him, he thinks it was less hassle than starting up his own modem business. "I said, 'This is an easy thing to do,'" he said in a 2004 interview with Network World. "I can just license this to people that are in the modem business. I don't have to start competing with them or set up my own distribution."
Tim Greene

SNA and OSI vs. TCP/IP

The long, slow and at times, colorful battle between TCP/IP backers and SNA stalwarts was one of the more acrimonious periods of time in the industry's history. IBM introduced the concepts and initial components of SNA in 1974 and by the mid-1990s it was locked in a do-or-die battle with IP's chief proponent - Cisco.

Cisco and the industry had some fits and starts in promoting TCP/IP and a real SNA alternative, at one point forming the Advanced Peer-to-Peer Internetworking (APPI) group to counter IBM's SNA advanced technology called APPN (Advanced Peer-to-Peer Networking). While APPI was ineffectual and folded in 1993, it planted seeds that would ultimately sow SNA's demise.

For its part IBM did just about everything wrong in upgrading older SNA users to APPN -- first it made APPN gear complicated and costly -- it even wanted royalties from potential third parties that could have helped establish the technology. In 1994, an IBM executive promised to "kill" vendors (mostly Cisco) and "eat our own young" before IBM would let any rival cannibalize SNA/mainframe business.

In addition, IBM threatened lawsuits over the use of some of its technology. While IBM had started losing customers, it still had more than 50,000 SNA installations, so its blustering had some power. But with Cisco licensing Big Blue's mainframe channel technology in the mid-1990s and the advent of Data Link Switching (DLSw) and tn3270 (which let SNA run over IP networks), the nails were in the coffin. Combine that with the fact that at about that time Gartner said users with SNA as their primary protocol (after about 1995) will spend a total of 20% more than IP users on training staff, hardware and software purchases, and administration.

You didn't need a Magic 8-ball to see the outcome. IBM sold most of its young to Cisco in 1999.

Open Systems Interconnect (OSI) technology backers were also making a lot of noise during this period. OSI products and services were based on an international set of standard protocols that were supposed to guarantee interoperability among all vendors and products. IBM and Digital Equipment Corp., in fact, were two of its chief proponents, despite the fact OSI ran completely counterintuitive to SNA and DECnet respectively. The U.S. government throughout the 1980s and 1990s mandated the use of OSI products but changed its tune in 1994 saying TCP/IP could be used instead. The TCP/IP juggernaut moved on and widespread use of OSI products never happened.
Michael Cooney

U.S. Department of Justice vs. AT&T

In the Ali-Frazier of last century's heavyweight telecom fights, the U.S. Department of Justice went toe-to-toe with AT&T after filing an antitrust action against the carrier in 1974.

Specifically, the Department of Justice accused AT&T of engaging in anti-competitive behavior and sought to break up the company. Invoking the Sherman Antitrust Act in its case, the government said that AT&T had monopoly power over America's telecommunications, and argued that the company should sell off some of its subsidiaries, such as manufacturer Western Electric and research arm Bell Laboratories, which would then be carved into even smaller companies.

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