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SubjectRe: [future of drivers?] a proposal for binary drivers.
Luke-Jr wrote:
> Fund a project to implement a software modem. While a "real" modem might have
> better performance, softmodems are more of a raw interface which can be
> better in the long run-- for example, if some new super modulation is
> produced for 1mbit over regular phone lines, you could possibly just upgrade
> your modem software for the new feature. You can also use the modem for voice

Except that is not going to happen because there are laws of physics
that must be obeyed. The phone line is encoded with 64 Kbps inside the
digital phone network so there is no possible way to modulate more data
than that. There is also the problem that the A/D converter ( which is
all the "software modem" is -- it's basically a stripped down sound card
) only runs fast enough to support 56,000 bps. Even if it could run
faster, that would place even _more_ load on the cpu.


> capabilities, and have your computer act as an answering machine while you're
> not using it for the internet.
> (Note this is all theoretically possible, and might require actual coding to
> achieve; just pointing out that softmodem isn't necessarilly worse than
> hardmodems)

They ARE necessarily worse than real modems in that they require a fair
amount of cpu cycles to perform all the DSP. IIRC, this also has to be
done in interrupt context to maintain the low latency required, which
lowers the interactive responsiveness of the system - even when you are
not transferring much data.


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