improving transport over lossy links ?
Brian Candler
B.Candler at pobox.com
Sun May 21 17:15:27 UTC 2006
On Sun, May 21, 2006 at 11:09:23AM -0400, Mike Tancsa wrote:
> The internal USR seems to correctly see the carrier drop and PPP
> hence sees it. However, the 2 external Intels I am experimenting
> with on the USB serial ports do not.
USB-serial adaptors tend to be very broken, unfortunately. I don't know
about under Windows, but under FreeBSD/Linux where drivers seem to be
reverse-engineered, several I've tried don't seem to handshake properly. I
tried two back-to-back to run a local pppd link and it failed (haven't had
time to debug that one)
IMO there's no substitute for a real COM port.
> (not sure why, but chats tx/rx are for all calls in the pas 216 days,
> not just this one). This is in the past 4hours. Perhaps with this
> one, I am just better off telling it not to try v.90.
A pair of analogue modems will never negotiate v90, as for this one end has
to be digitally connected (typically T1/E1 trunk, although in theory you
might be able to find a modem which is physically connected as ISDN BRI but
which supports v90 analogue modulation)
The best you'll get is v34bis (33.6K)
Regards,
Brian.
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