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From: igb@fulcrum.bt.co.uk (Ian G Batten)
Newsgroups: comp.mail.uucp
Subject: Re: Using UUCP over international phone lines
Keywords: satellite packet-size acknowledgment delays
Message-ID: <K87^81&@uzi-9mm.fulcrum.bt.co.uk>
Date: 24 Jan 91 11:09:48 GMT
References: <267@fgh.fgh.oz.au> <1991Jan24.033322.7924@iguana.uucp>
Sender: isode@fulcrum.bt.co.uk (Isode Hackers)
Organization: BT Fulcrum, Birmingham
Lines: 19

In article <1991Jan24.033322.7924@iguana.uucp> merce@iguana.uucp (Jim Mercer) writes:
> 2) use another protocol.  if the link is kept clean by hardware (MNP?)
>    you could use something like the x, f or e protocols that do less
>    error checking and basically just stuff the file down the pipe with
>    a checksum at the end of the file.

Don't do this unless you have ``f''.  ``e'' doesn't even send a checksum
and relies on a TOTALLY reliable link layer.  That means that the error
rate in your modem<->host cables, UART overruns, etc become real issues.
``x'' requires the ability to send zerolength packets to reflect end of
file.  You may have trouble doing this over a modem (or indeed over BT's
PSS or other X25 offerings).  ``f'' does send a checksum, but you should
be aware that it expands anything with the top-bit set to two bytes,
being intended to work over 7 bit links.  And you probably don't have it
anyway.

I get 700cps transatlantic with no fiddling with my trailblazer.

ian