Re: Very fast IP, no ATM...

[Paul Bryant <]

At 15:36 03/12/96 +0000, you wrote:
>
>
> >Interestingly BT claim that their network will never overload as they charge
> >for local calls - ie ration by cost. The corollary is that if the network
> >becomes overloaded they raise the cost. 
>
>
>a voice network nowadays is pretty easily overengineered anyhow

Well - some countries.
>
>afterall, people don;t spend more than 8 hours a day on the phohne,
>and if one person is speaking, the other is silient, so you only have
>to support 12th of the worlds population of voice traffic - if yo udo
>silence suppression

I think you may be wrong. On a national network (modern) the network is
digital and once you are past the codec you don't know whether the call is
voice or ISDN data. If you start to do silence suppression on ISDN I suspect
that things may go wrong. Internationally you are right - not only do you
have silence suppression but also voice compression to 16K. That is why on
international ISDN you have to dial 000 rather than 00 for an international
call to ensure digital 64K end to end. Interestingly this doubles the cost.
Taking into account speech may be compressed and silence suppressed double
the cost looks cheap (but don't tell BT). I suspect that 28K modems do not
work well internationally and I suspect that the new 56K modems (do we call
them modems?) do not work at all. Am I right?
>
Paul Bryant - Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX, UK
Mail P.Bryant@localhost 
Tel.+44 1235 445 267 Fax. +44 1235 446 626