This is getting to be an interesting conversation.
On Fri, 31 Jan 1997, Mike Bilow wrote:
> I think you misinterpreted my comments. My objection is that people use the
> guarantee of delivery provided by AX.25 as a kind of crutch to prevent them
> from having to address RF link quality and similar issues of the kind you
> mention. Furthermore, there are a lot of problems which simply cannot be
> solved by upgrading RF links, such as "hidden transmitter syndrome," and these
> kinds of problems will have to be addressed by time slotting or other more
> sophisticated techniques.
That I suppose is one of the reasons behind DAMA. People report some very
good results with BTMA and regenerative repeaters which place much less
stress on protocol engines and radios that DAMA does.
> There are advantages and disadvantages to this. Unlike a stateless datagram
> protocol such as TP, switched circuit protocols such as ROSE require a fair
> amount of state information to be retained at intermediate systems. This
> places significant burdens on running routers in little TNC boxes.
What I envisaged was a cut down version of ROSE. One where the end user
TNCs didn't implement through routing like a real ROSE node, then the
only state information they would hold would be for themselves. I have to
say that the amount of information held on each through link with ROSE is
really quite low and the amount of code and data required is less than
that required on a datagram based system because of the increased
complexity in the transport layer that they have.
> Oh, then I agree completely. The whole idea of supporting a non-protocol L3
> protocol was clearly a mistake that is at the root of this problem.
Looking back at old ARRL CNC papers, an attempt was made to produce an
AX.25 L3 a short while later, in effect ROSE. However like everything in
packet radio, forget the official protocols, he who implements first, wins.
> -- Mike, N1BEE
Jonathan
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