On Tue, Oct 6, 2015 at 8:36 PM, Johnny Billquist <[email protected]> wrote:
> Right. I suspect Rich was actually thinking of the 7 layer OSI model, > which DEC tried really hard to implement. > insert >>eventually<< in there and I agree. In the first few generations of DECnet, as Rich points out, DEC was no different than anyone else and had a closed networking system and it was not that clean. By DECnet phase III many lessons had been learn and it really was a nice subsystem. However, I've always felt that one of the failures of DECnet was the dogged adherence to ISO protocol later made them ignore the "IP" part of the the Internet protocol for too long - because in fact OSI did not really have it in its model. By the time the ISO guys added intra-networking (network of networks - or what I referred to as "Dave Clark's observation"), Metcalfe's law (the value of a communications network is exponentally proportional to the number of things connected to it) it was too late. And by then the US Gov had paid for enough IP/TCP implementations and there were so many on the Internet that even IBM and Microsoft could not catch up (although they too tried). > (And no, TCP/IP do *not* follow the 7 layer OSI model.) > Amen, not by a >>long<< shot. You could sort of map it, and we all tried to explain the IP stack in those terms, but you are so right. That said, one of the problems with the OSI model was it did not do a good job with the "network of network" concept which was what made the Internet take off because it enabled Metcalfe's law to be in effect. It seems to obvious today, but at the time, it was not so clear. A lot of very smart people believed in closed networks. Clem
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