On Apr 7, 2010, at 11:03 16AM, Joe Greco wrote:
On Wednesday 07 April 2010 07:18:57 am Joe Greco wrote:
To me, this is a Dilbert-class engineering failure. I would imagine that if you could implement a hub on the network card, the same chip(s) would work in an external tin can with a separate power supply. Designing a product that actually exhibits a worse failure mode than 10base2 is ... strange to me.
I have in my gear museum a fairly large box with a couple of this type of 'hub on a card' installed. And in this particular case, it made perfect sense, as the box is an Evergreen Systems CAPserver, and has 16 486 single-board computers tied to two 8-port hub cards (two ports on each modular plug, too), with....wait for it... a 10Base-2 uplink. These were used mostly for remote network access and remote desktop access.
If you want more data on this old and odd box, see http://www.bomara.com/Eversys/capserver2300.htm
I can see a hub card being useful in an old NetWare server setting, though, since if the server went down you might as well not have a network in the first place, in that use case.
Certainly. I can come up with a bunch of reasonable-use scenarios too, but most of the people here will have run into that awful situation where a product is used in a manner that isn't "Recommended".
In this case, I know that some of these cards were marketed in the same manner that workgroup hubs/switches are marketed; you would daisy-chain these stupid things so that your PC would feed the cubes right around you and then have an uplink and downlink a few cubes to the next "hub".
When I had the need to wire a building around 1987, I opted for the multiport 10Base5 repeaters that DEC made -- they were called DELUAs, I think. I'd had quite enough of distributed single points of failure, thank you.
Remember, it was this strange time when people were uncertain about how networks were going to evolve, and what the next thing would be, and even then, 10baseT was being deployed over Cat3 (sometimes recycled/ repurposed), so any sort of "enabling" gadget such as these cards had a tendency to be abused in various ways.
Right -- the wire and pin assignments for 10BaseT and 100BaseT were designed to permit sharing the cable between Ethernet and phone.
Two ports on each modular plug, though.... (shudder) ;-)
Hey, I had that in my house on my 100BaseT network, till I upgraded to gigE and had to give in and buy another switch. (Sigh -- home network configurations of NANOGers. I'm contemplating putting in VLANs now...) --Steve Bellovin, http://www.cs.columbia.edu/~smb