The drive to revamp the ARCnet local area network topology by early next year is running into resistance from loyal users, whose battle cry could be, ”If it ain’t broke, don’t fix it.”

The ARCnet Trade Association (ATA), sponsor of the revamping effort, is seeking to boost the speed of ARCnet from 2.5M bits per second to 20M bps, increase the efficiency of network transmissions and expand the maximum size of ARCnet networks.

The improvements are aimed at strengthening ARCnet’s image as a viable alternative to Token-Ring and Ethernet local area network topologies.

However, some industry observers have said that by redrawing the ARCnet formula, developers may be throwing away the features that attracted users to ARCnet in the first place. The network’s ease of installation, reliability and lower cost are its primary strengths against competing technologies, they said.

”[ARCnet] is like a [Volkswagen] Beetle,” said Paul Nelson, a networking consultant for Venture Development Corp., an industry-analysis firm in Natick, Mass. ”To change would be a mistake,” he said.

The process of making ARCnet faster and more efficient will probably make it 50 percent more expensive as well, ATA President …