Get rid of the past
Last week I reformed 2 old COMPAQ computers from an old client of mine.
They were messing up the machine room and I decided to get rid of them once for all.
Nevertheless I accorded them some attention, something like an ancient farmer should have done with old working horses before sending them to the butchery (Imagination ...)
For the youngers, SFT III stands for System Fault Tolerant, III being the upper level.
The principle was to create a virtual server upon two physical ones.
The 2 computers were doing exactly the same thing and one of them was responding the client request after ensuring they were coherent.
A pretty smart system !
They were 2 LAN adapters in each computer : a 10 Mb Ethernet link for the standard LAN attachment and a Thomas Conrad 100 Mb ARCNET adapter for the dedicated link. And guess what : first of I kept the TC cards for me as souvenir and second I would like to emphasize on the following :Nevertheless I accorded them some attention, something like an ancient farmer should have done with old working horses before sending them to the butchery (Imagination ...)
But have some gratitude
These machines has been used for years with NetWare 3.11 SFT III then NetWare 4.10 SFT III.For the youngers, SFT III stands for System Fault Tolerant, III being the upper level.
The principle was to create a virtual server upon two physical ones.
The 2 computers were doing exactly the same thing and one of them was responding the client request after ensuring they were coherent.
A pretty smart system !
Stumbled upon to something interesting
The 2 computers were linked with a dedicated high speed LAN connection, and that's the point I stumbled upon more particularly.- both cards were manufactured in 1994, EISA bus.
- the Ethernet one was a full length card - remember the one that occupied all the place from front to back of a standard PC case - and it was full of chips, no room left at all on it !
- the ARCNET one was a short one with one main chip and a plenty of room on it.
So what ?
Well, ARCNET technology is able to make circles around Ethernet.It has been and it is a much more efficient technology, you can integrate it on some 25000 transistors or so far, against perhaps 250000 for Ethernet, beside ARCNET protocol (layer 2) is much more efficient and one which is precisely able to met isochronous requirements some traffic like voice are begging for.
In fact what is happening with Ethernet ?
The original layer 2 protocol CSMA CD is no more used, it is been killed by use of switches in which we are incorporating - by software - the intelligence which is lacking to layer 2 protocol.What is left to Ethernet is a frame format, and layer 1 encoding and transmission.
What happened to ARCNET ?
Why the technology almost disappeared if it were so good ?Simply MARKETING.
But I don't want to mess up everything's, I will explain what marketing is really in another post.Stay tuned !
Notice the gentleman on the photo ?
It's John Murphy ARCNET Chief Architect, let pay his legacy a little visit :
Arcnet Resource Center
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