Conference 7.286::fddi

1922.0. "Tuning issues in a Switched FDDI env." by MXOC00::GALICIA (GUILLERMO GALICIA) Thu Jan 04 1996 12:24

Hello,

At the begining, Happy New Year for all of you.

We are working in a project for an important mexican bank where the idea is to
solve their  requirement of a High performance backbone for their finantials
applications.

At this moment, they think ATM is not ready and they consider that network
technologies as Fast Ethernet or Switched FDDI are more cost/effective
solutions.

Our solution is based on a Gigaswitch/FDDI and we are in competition against a
box from Cisco Systems (Catalyst Switch). They will use their development group
envionment in order to run some Sybase Client/Server applicatons located in a 
couple of systems: One AlphaServer 1000  with Open VMS V6.2 and one Alphaserver
2100 with Digital UNIX V3.2C, both of them are configured in a TCP/IP Network.
The environment that will be used are the following:

1) Both Database Servers in a Switched FDDI environment through a 
Gigaswitch/FDDI and with the clients (PC's) in a Shared Ethernet segment 
(The Ethernet segment was integrated through a DECswitch 900EF).

2) Both Database Servers in a Fast Ethernet environment and the Clients (PC's)
in a Shared Ethernet segment. Both of them will be linked through  the Catalyst
Switch.

Regarding the first case, the NIC's used are a couple of DEFEA (SAS with MIC
connectors and with Firmware revision 2.3). The Alphaservers and the DECswitch
900EF are connected to the Gigaswitch through a couple of  DAS cards.

Obviously, before to run the tests we have been making some File transfers
between both servers (FTP) with the following results:

File size (MBytes) Time elapsed (seg) Kbytes/seg  Network Topology
7.4                      7                 1000     Switched FDDI
7.4                      16                 470     Shared Ethernet(*)
72.3                     75                 950     Switched FDDI
72.3                     123                587.7   Shared Ethernet(*)

(*) Before to integrate the Gigaswitch, both Alphaservers were located in a
Shared Ethernet Topology. Full duplex feature was not used because I just
find how to do it on the Unix Server (fddi_config utility).

Are there some special tuning (as example in the network parameters) we must to
take in account in order to improve our results?

As you can see we got 1 Mbyte/seg in the best case. Obviously  these are not
the results we were waiting for.

I would really appreciate any comments,

Thanks in advance and best regards

Guillermo.