* ISDN redux
Some topics and technologies seem to hang on forever, but we’re not sure whether ISDN Basic Rate Interface service is one of those. This came to light this week when we got a note from someone who was (evidently) browsing the newsletter archives and noted that we had asked more than a year ago for the last person using BRI service to turn the lights out.
As a quick bit of background, ISDN was envisioned as the future of integrated voice and data networking in an era of terminal-to-host text-based interactions and when the processing power and storage in a typical computer was less than that found today in an iPod. However, technology took a sharp turn and the era of packet data began in earnest.
ISDN was introduced in two flavors. There was the residential and small office version known as BRI, which consisted of two 64Kbps TDM “Bearer” or “B” channels for traditional PCM voice plus a 16Kbps packetized “Data” or “D” channel for call control and other data; thus the nomenclature 2B+D. But hey! Who could POSSIBLY use more than 16Kbps for data in a home environment? Then there was the Primary Rate Interface (PRI) designed for interfacing to PBXes with (in the North American format) 23 64Kbps Bearer channels and a single 64Kbps D channel; thus 23B+D. PRI service also exists in a 24B format, since a single D channel can provide call control functions for more than one PRI.
About a year ago, we found that there were still a few – very few – users who still had BRI service. But they were very few and far between. So now, as a service to the recent inquiry, we’re looking to see whether there’s anybody who is still using BRI service – and whether any service providers are interested in offering the service.
