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Conference 7.286::fddi

Title:	FDDI - The Next Generation

Moderator:	NETCAD::STEFANI

Created:	Thu Apr 27 1989
Last Modified:	Thu Jun 05 1997
Last Successful Update:	Fri Jun 06 1997
Number of topics:	2259
Total number of notes:	8590

1955.0. "PEswitch900, vs. ????" by CIVPR1::MARKIS (Depends on Your Perspective, Ofcourse ...) Mon Feb 12 1996 20:25

NOTE:  Read this thoroughly before tearing it apart.
       (I know it has flaws, but then so do I)



I have a customer that has a large number of "non-dec" repeaters stacked up 
within his Computer room to interface all the Servers there and the local 
Offices (on that floor).  They then have 10basefoil to the various floors
to feed 4 - 6 stacked Repeaters that feed all of the offices on those 
floors. 

"Ideally", I would like to recommend a DEChub 900 for the computer room.

"Realistically", they don't have the Budget for a total rewrite, soooooo ...
I thought that it might be a good idea to recommend a couple of 
PEswitch900TX's to frontend the Servers (using DEF1H-AA DEChub one's) to a 
small FDDI Ring.

On this FDDI Ring, would be:  1) other PEswitch900TX's with each Port 
connected to a "non-DEC" 10baseT repeater to feed the local Offices, on 
this floor.  2) a DECconcentrator900MX which would feed the Fiber to the 
various floors where PEswitch900TX's would feed the 4 - 6 Repeaters there.

The problems I see in this are that the PEswitch900TX only supports 64 
addresses, however, it's faster than using DECswitch900EE's or EF's, which 
are Bridges (but support 8,000 addresses).


Recommendations are accepted (remember they don't have mutch of a budget, 
and we don't give much of a tradein for nondec stuff).


Chris

T.R	Title	User	Personal Name	Date	Lines
1955.1	PEswitch ~= DSwitch (perfwise)	STKHLM::WEBJORN	Gullik Webj�rn Network Advisory	`Tue Feb 13 1996 06:44`	18
	I was under the impression the PE-switch is just a costreduced DS900EF where the PMD's are removed and learning cache reduced from 8000 to 64, i.e. no speed difference otherwise. (correct me if wrong!) Are servers 'weak' enough so it does not make sense putting them on the ring? We suggest DecConcentrator 900 with UTP to connect the servers, and FDDI/UTP cards. Con is then connected to DS900's feeding some 30-100 clients per ethernet depending on applications. For connection to 'other make' repeaters and hubs, DS900 EF in a hub-ONE is often a costeffective distributed solution. Gullik
1955.2	TX had Lobodomy, EF/EE not enough UTP Ports	CIVPR1::MARKIS	Depends on Your Perspective, Ofcourse ...	`Tue Feb 13 1996 18:17`	47
	Gullik > I was under the impression the PE-switch is just a costreduced DS900EF > where the PMD's are removed and learning cache reduced from 8000 to 64, Definitely, the PEswitch is cost effective, except for the Lobodomy. The "EF" has 2 AUI Ports and 4 UTP's. I'm looking for 6 - 12 UTP's for interfacing with User Distribution, no "AUI". > i.e. no speed difference otherwise. (correct me if wrong!) I have no Idea about the Speed difference, if someone knows more, please jump in ... > Are servers 'weak' enough so it does not make sense putting them on > the ring? Servers are NOVELL PC's (Gateway 2000's), VAX6410, VAX8650. Not worth the cost of an FDDI Card, probably couldn't push it fully, anyway ... We're negotiating on Porting their Applications to ALPHA (VMS or NT). Then we could plug more directly into the FDDI Ring with the New Systems. > We suggest DecConcentrator 900 with UTP to connect the servers, and > FDDI/UTP cards. Con is then connected to DS900's feeding some 30-100 > clients per ethernet depending on applications. ---- See above hardware ---- Presently the Hardware is fighting over a single 10Mb HUB Backbone, so spreading 30+ users out onto their own 10Mb segment from FDDI Backbone, would be a blessing. YES/NO ???? > For connection to 'other make' repeaters and hubs, DS900 EF in a > hub-ONE is often a costeffective distributed solution. I'd love to use the EF (or EE), but for those "AUI" Ports How would the "TM" or "FP" using the "FDDI DEChub-ONE" be for driving the 'other make' repeaters and hubs ???? Especially since the feeds are 10baseFOIL and/or 10baseT ???? Chris 8^)
1955.3		STRWRS::KOCH_P	It never hurts to ask...	`Wed Feb 14 1996 07:26`	17
	Well, you talk about UTP and then about fiber feeding some floors. You may benefit from the new FiberSwitch 900EF. It is being announced in April. The FiberSwitch 900EF looks like a PEswitch 900TX, but instead of UTP ports, it has FO ports. Also, it has support for 8k Ethernet addresses, just like the 900EF. So, for this customer create a UTP ring in the computer room using DEF1H-AA units with TP-PMDs. Then use the FO ports to connect to the closets with the installed FO runs. Use a PEswitch 900TX in the computer room for the servers. You get can use the AUI on the FiberSwitch 900TX if you need another media. Then, when you upgrade the servers to Alpha, put a DEFPA-MA (DAS UTP) card into that machine and hook it directly into the ring.
1955.4	PEswitch is a store & forward like its EE, EF cosins...	NETCAD::BATTERSBY		`Wed Feb 14 1996 11:50`	8
	>I have no Idea about the Speed difference, if someone knows more, please >jump in ... There is no difference between the PEswitch and the EE or EF. They are all store & forward bridges. The PEswitch passes Ethernet packets at wire speed just like the EE & EF do. Bob
1955.5	Thanks (Who do I contact for Advance Pricing)	CIVPR1::MARKIS	Depends on Your Perspective, Ofcourse ...	`Mon Feb 19 1996 11:27`	9
	Thanks .1, .3 & .4, I'll look forward to the "APRIL" announcement, if I can possibly get pricing sooner than that. They would probably not be able to order any sooner than April, but would want to know pricing to get the "Wheels Turning" (government) ...... Chris 8-)
1955.6		STRWRS::KOCH_P	It never hurts to ask...	`Tue Feb 20 1996 07:43`	2
	Conact Alice Hassey @LKG.