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18. Dream A Little Dream – Beyond Copper Wires   8/23/12 by Dave Immer

After a brief vacation it’s time for an installment of my new segment: DATAGRAMS – Messages From the Future!!

The underlying characteristics of the PSTN (the Public Switched Telephone Network, of which ISDN is a subset) are what provide us with the all-important synchronous circuit-switched data stream that distinguishes ISDN from IP.

The Present: A primary technical obstacle to providing switched digital service is that it is delivered over twisted copper pair wires. This is part of the legacy technology that has not been continually upgraded like the internet infrastructure has.

The Future: Twisted copper will phase out. The synchronous data stream will be delivered over the same cable or fiber that we get our internet by. There will be no need for physical installation of a digital line-just an added service to your existing bundle.

The broadband modem could provide the S/T or U-interface function and the user would be presented with a standard phone jack. The circuit would interface with the PSTN and enable both voice and data mode calls.  (Don’t ask me the details here. I just do the vision part...)

When fiber is widely deployed, we will see this happen. Eventually internet bandwidth will become so cheap and plentiful that everyone will be skyping live un-coded linear audio and video. (Alas, network latency will not go away.) But for stable, low latency remote broadcast quality media we will still need the PSTN with it’s 64kbs channel chunks in our production chain.

Let me know if you have  questions or comments about the PSTN.  Thanks,

-Dave