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Connecting to CERN from Home: ACB Service over ISDN

  John Ogilvie IT/CS

Overview of the ACB ISDN Service

ISDN (Integrated Services Digital Network) is an extension to the public telephone network, which guarantees higher speed (64 or 128kbps) network access.

An initial ACB (Automatic Call Back) ISDN service, based on a small ISDN router connected to a home computer (PC, Mac or Linux) via an Ethernet card is available. It currently offers only Internet access (direct access to NICE and Appletalk files is under investigation). To use ISDN your home must be cabled for digital access to your local Telecom supplier.

The ACB ISDN service is offered in addition to the existing ACB modem service.  The ACB modem service will continue to be operated and improved (56kbps modem access is planned for later this year).

Choosing between the ISDN and Modem ACB services

ISDN Advantages: Modem Advantage: Note 1: ISDN provides 2 guaranteed digital channels at 64kbps, whereas actual throughput achieved by 56kbps modems is typically around 40 kbps (depends on the line quality). In addition, 56kbps modems are asymmetric with only 33.6kbps in one direction (home to CERN).

Note 2: Installing ISDN in your home costs significantly more than an analogue telephone line. ISDN monthly charges are roughly equivalent to the rental of 2 analogue lines.

For more complete information, please see the ACB Web pages:

For matters related to this article please contact the author.

Last Updated on June 24th, 1999 at 16:52:04
Copyright © CERN 1999 -- European Laboratory for Particle Physics