[Search for users] [Overall Top Noters] [List of all Conferences] [Download this site]

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

831.0. "DAS FDDI controller for Turbochannel" by QBOU04::QBOP01::A_MICHEL () Thu Jan 14 1993 18:19

I have to answer a big tender($500K) for the Canadian Federal Government and 
I need somebody's help on this one.

In the bid, the customer is asking for a DAS FDDI card that goes in the 
TurboChannel bus of an Alpha workstation(3000-400, Sandpiper).I personnaly 
understand perfectly all the limitations of doing so instead of using a SAS 
controller(like the 700), but we HAVE to bid DAS controllers.

1 - Is there plan to get any DAS board(Turbochannel) that will fit in an     
Alpha Workstation ?

2 - It is not really possible for me to put two 700(SAS) controllers because 
I have only one Turbochannel slot available because of the use of other 
Turbochannel controllers.

3 - Is there some third party FDDI DAS controllers that would fit in the 
Turbochannel bus.

I will appreciate other suggestions or comments if you have some.

Many thanks in advance.

Andr� Michel
Sales support Qu�bec, Canada 
T.RTitleUserPersonal
Name
DateLines
831.1KONING::KONINGPaul Koning, A-13683Fri Jan 15 1993 12:1010
How about some background -- why is the DAS required? 

If you don't have room for two adapters, would it be possible to use a Flamingo
instead (which has more slots)?

One obvious problem is that a single width module is very small, and it's hard
to imagine that another PHY could be squeezed onto it.  That's one reason why
we don't have a DAS version...

	paul
831.2DEFTA - SAS onlyDELNI::ONEILLMon Jan 18 1993 11:2125
I am the Product Manager for DEFZA and a new DEFTA controller.
DEFTA is a single module (DEFZA is two) but both designs
take up one slot only.  Even if we decided to do DAS
you would have a slot limitation based on your feedback that all
slots have TURBO options except one.  If we implemented 
DAS today on the newer controller, it would have to be 
a 2 board set so we are back to where we started.  

Is the customer looking at the higher end WS or server
(Flamingo - DEC 3000 Model 500 that has I believe
6 TURBO slots? or is it because you are configuring a 
Sandpiper - Model 400?)

There is no third party FDDI-to-TURBOchannel controller
that I am aware of.  There is a VME controller and you
could consider some of the FDDI-to-VME DAS controllers
on the market.  The performance would not be as good and they
tend to be pricey.  If customer is trying to save the 
cost of connection to concentrator, you'll find the
cost of VME-to-TURBO controller plus VME-to-FDDI
more expensive.

There is no plan at this time to support DAS although
we have had numerous discussions about it.  Can you help me understand
why DAS is so important to this customer?  
831.3Its high availabilty!QCAV02::RANGARAJTue Mar 30 1993 07:2219
    Hi,
    
    I too need a DAS adapter and reason why customers are insiting upon it
    to connected them to multiple concentrators through dual homing. I
    believe that in the case of VAX's with multiple SAS devices, VMS
    provided the capability of failover of one SAS device to another and
    the two sAS devices where in turn connected to two different
    concentrators. Since we are now in the age of Alpha and a few of us
    sell OSF/1 based systems, if the same functionality can be achieved, i
    suppose that is fine.
    
    So the bottom line is basically availability!
    
    Hope we have a solution for this problem.
    
    Regards,
    
    Raj
    Digital India