dick@ucsfcca.UUCP (Dick Karpinski) (03/19/86)
rhk -> net.lan Re: connecting Ethernets 18 Mar 86 I need to connect two Ethernets. I have considered gateway machines but rejected them as too big and expensive. The VitaLink TransLan is also big & dear and limits the throughput, though the filtering and self-maintenance of address tables are both excellent features. DEC may have something similar, now, but I bet I won't love that price either. Applitek's seems likely to be cheaper, but it is also brand new and I don't know of any user experience with either box. Have you used a protocol independent remote bridge? I will be happy to post or mail my compilation of your experience with any of these or other similar devices. Below these, are local bridges in the $8-15k range. They are NOT protocol independent and often require to be told who is where or to be explicitly addressed as an intermediary in any cross net message. Too expensive and too restrictive for my taste. Would anyone care to set me straight on why I should love them? The cheapest alternative which is transparent looks to be a buffered repeater. It won't filter at all but is said to work at full speed. Does anyone know of a viable alternative ($6k or less) to this little box from U/B? Has anyone used one of these? Any problems? One with filtering would be very attractive to me. Perhaps a network watcher could instruct it to stop sending packets for so-and-so this way, to reduce the maintenance effort by people while not requiring the repeater to be very smart, just fast. Send mail. I love mail. Dick -- Dick Karpinski Manager of Unix Services, UCSF Computer Center UUCP: ...!ucbvax!ucsfcgl!cca.ucsf!dick (415) 476-4529 (12-7) BITNET: dick@ucsfcca Compuserve: 70215,1277 Telemail: RKarpinski USPS: U-76 UCSF, San Francisco, CA 94143
gp@lll-crg.ARpA (George Pavel) (03/21/86)
Here at LLNL we have tried both Applitek and DEC Ethernet bridges. They both
work well at the basic job of filtering packets between Ethernets. The DEC
bridge is currently faster. The cost varies depending on how you are tying
the Ethernets together. We tie them together over a broadband cable system.
The DEC bridge is made to tie directly to two Ethernets, or to optical fiber
Ethernet repeaters. The Applitek bridge ties to Ethernet on one side and
to Applitek's proprietary Unilan on the other, so you need at least two Applitek
units to tie two Ethernets together. Unilan can run on baseband
(Ethernet) cable, broadband, or optical fiber.
In our configuration, a DEC bridge must be coupled with a broadband Ethernet
transceiver to go over the broadband cable. This combination comes out
somewhat cheaper than the Applitek unit on broadband. However, broadband
Ethernet is very limited in distance -- about 1 mile; Applitek broadband units
are conservatively rated to 5 miles and have been made to work to 15 miles.
Rough list prices:
DEC LAN 100 Ethernet bridge < $ 8,000
Broadband Ethernet transceiver < 5,000
Applitek broadband bridge 13,000
I also recently saw an announcment that CMC now has an Ethernet bridge that
is presumably equivalent to DEC's.
George Pavel ARPANET/MILNET: gp@lll-crg
Lawrence Livermore National Laboratory UUCP: {ihnp4,seismo}!lll-crg!gp
P.O. Box 808 L-61
Livermore, CA 94550
(415)422-4262