| One of my customer is claiming that access (disk backup) from an
Ethernet system to a FDDI host is having priority to a similar tranfer started
between the same server and a client on FDDI. It looks like the FDDI starts when
Ethernet is finished (both copy are started simultaneously).
The Servers are HP systems and most of the FDDI to Enet Bridges are
DEFEB. (DECbridge 500).
What I was able to measure is the fact that in normal circumstances HP
systems are using Priority 7 while all other FDDI systems including the bridges
are send message with priority 0.
Priority on FDDI looks for me for the moment quite complicate but at least I
should expect that HP to HP should be faster that HP to Enet via DECbridges,
which is not the case, so there must be something else.
Incidently I when to the Restricted Token parameter (Timer) on the DEFBA
(DECswitch 900 EF) which for me is preventing system using resticted token to
monopolise the ring. But is it possible that one of our system is using this
restricted token in the time frame allowed by the timer and so that we can
explain that Enet to FDDI can be faster than FDDI to FDDI.
There is no FDX FDDI configured and from the litterature I read that restricted
token is not used.
Can someone clarify that for me ?
Thanks in advance,
Robert Vandenberghe
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