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Re: [HLL] Re: VP1 Comparison



Status: RO
Content-Length: 1412
Lines: 28

On Tue, 6 Jan 1998, Volker Ernst wrote:
> 
> We would like to use a standard-144-modem.
> These modems use V32bis and are therefore synchron "on the line".
> However VP1 has a direct "synchron" connection to the modem-chip.
> In our case this synchronous data is converted to asynchron.
> While this does not change the baud-rate (we can still use gsm-full-rate),
> it changes several aspects for frame-synchronisation.
> These differences to aquire and maintain sync were what i meant.

You will find that said differences will push your protocol overhead just
high enough to no longer being able to use the GSM full rate codec. But I
agree with you that anything that will run on just a standard Pentium with
a standard modem will have to use an async protocol.

Since I apparently missed the beginning of the discussion, would you
please explain to me where the device your are building gets into play? If
you run the codec and the crypto on a regular PC, what do you need the box
for? Or is the box only used for stand alone mode when you don't have a
PC? 

Could perhaps one of you write up the design requirements of the system? A
very rough draft would be fine. I don't think I yet fully understand what
you are trying to do.

Thanks,
-- Lucky Green <shamrock@cypherpunks.to> PGP v5 encrypted email preferred.
   "Tonga? Where the hell is Tonga? They have Cypherpunks there?"