[A86] Re: Async Link Routine
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[A86] Re: Async Link Routine
Realizing that at 9600 baud, your max transfer rate is 960 bytes/second, and
the smallest TCP/IP packet will be about 44 bytes, with no data, you get
maybe 20 packets at most. When you have that many errors, it isn't going to
work. Checksums on TCP/IP really aren't perfect. Theoretically, after
enough data has been transmitted, some of it will be wrong. You have the
chance that the checksum will be correct for incorrect data. The checksum
is really designed for error checking on the protocol level. The link layer
needs to have it's own error checking.
The best way to handle something like this is a shell account that you can
dial into directly. You would have much, much less lower latency, and it
would actually be usable. Ever wonder why you could easily use a BBS at
2400 or 9600 baud, but an SSH connection on a modem is pratically unusable?
That's because every keystroke requires 90-100 bytes of data. That doesn't
seem like a lot for a "fast modem", but it still means you get 200-250ms or
higher pings. I sure type a lot faster than that. It's much better when
your keystroke and the response arrive immediately.
> Is there any sort of software flow control or error correction in the
> protocol that you could take advantage of?
> If you're putting a higher level network stack on top of it, could you
> just ignore errors at this level and let the checksum or whatever take
> care of it?
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