Re: Random musings... (Was Re: Long filenames in DOS server)

Hi Andy,

Andy Valencia wrote:
>
> Perhaps the easiest way would be to have a standard mount point (and it
> would still use TCP/IP if nothing was mounted at that name). So any server
> which could handle the needed messages could be used. I could then imagine
> a shim which could turn these into (raw) Ethernet messages--but it would
> have to handle things like MTU limitations (some sort of scatter and
> reassembly, I assume). Or it could be a teeny server which turned it into
> bytes out a UART. You get the idea.

I would guess that scatter and reassembly shouldn't be too hard - as
we're only interested in connections then perhaps something like what I
believe IL does sounds OK (reliable packet delivery - rather than
reliable byte streaming). I suspect that we could compress the network
and transport layers down to something utterly trivial if there's no
need for routing.

Any thoughts on using Ethernet CRC-checking instead of protocol-level
checksums too? I've just been reading about some Sun Ethernet cards not
doing things quite right and this getting through with a UDP
implementation that didn't checksum (I don't know the full details
though - it was a h/w problem apparently), but this would help with
speed if we think it's OK. If not, any thoughts on a prefered checksum?

The teeny server idea sounds like it'd be SLIPish, although PPP ought to
be a reasonable bet for comms over a UART (I've not done PPP yet though,
but it only looks like a couple of days of work). SLIPish sounds more
in keeping with the objective of course (lighter weight altogether).

> I'll convert the current C library shim (hard coded to IP) if this sounds
> useful to anybody. I'd prefer to do it in concert with somebody actually
> exercising an alternative transport.

Alternative transports I can do :-) I designed my code to support a
rather generic view of ISO-layered comms stacks because I support so
many peculiar embedded protocols to pay the bills, although I've not
done an Ethernet based alternative yet.

I'm on holiday from the end of the week, but as soon as I'm back I'll
start designing something and run it past the list for comment.

                                Regards,
                                Dave
Received on Tue Jul 18 13:25:32 2000