| > 1) Can we connect a repeater which connected with serval ethernet nodes
> to one of the Front panel port of PEswitch 900TX?
As long as the total number of Ethernet end stations connected to
all of the Ethernet ports of that PE does not exceed 64. More than
that will still work, but cause unnecessary flooding.. not
recommended.
> 2) Just want to clasify that in a DEChub 900 we can upto 8 PE switches and
> that gives us upto 48 ethernet ports each with 10Mbps, it is correct?
You need to check whether the hub power budget allows for 8 PEswitches.
I think it does, but can't say for sure.
> 3) In 2), do we have to connect the PE swicthes via the backplane using
> FDDI or the switch will be automatically done by default?
Not done automatically, you need to configure them.
> 4) If we have DEChub90 modules in the same DEChub900 as the PE switch,
> then can the DEChub90 modules talk to devices on PE ethernet ports
> without any DECswitch/other 900 modules? How does it happen? Does it go
> through the thin-wire segment of the DEChub900?
They can talk via the thinwire, as long as you configure them first.
Just connect one of the PEswitches to the thinwire. Note that it
will take away one of its ethernet ports, and also every end station
on the 90 will subtract from the 64-Ethernet station budget of that PE.
Anil
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.-2
8 PEswitch900TX in one DEChub900MS to get 48 Ethernet ports (48 colision
domains)...I'm not sure.
The PEswitch900TX has the FDDI ports directed to the backplane and
therefore needs two flex channels per port. To connect 8 PEswitch would
require 16 flex and there are "only" 15 availables (14 in the lower
connector and 1 on the upper connector). In that case only 7 PEswitch
can be used. The power budget is OK: 7x 50.5=353.5W plus 15(HUB)=368.5W
The only way to get 48 ethernet ports is to use 6 PEswitch and 2
DECswitch 900EF (one A port to external on one 900EF, one B port to
external on the other). The ring can be either closed with an external
connection or join an existing ring. BUT, the problem is the power
budget:
2 x DEcsitch900EF = 2 x 67.5 = 135 W
6 x PEswitch900TX = 6 x 50.5 = 303 W
1 x DEChub900MS = 15 W
= 453 W
I've seen somewhere else that we can create 48 collision domains within
a DEChub900 and I'm afraid that this statement is wrong.
Do you agree..??
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| It is a true statement that 8 PEswitch 900TXs cannot be configured
into an FDDI DUAL RING on the backplane. That is due to the fact
that we only support DUAL RING connections onto the backplane today
and every connection between modules requires TWO channels. In order
to complete the dual ring 16 channels would be required and we only
have 14 in the 160 pin (lower) connector.
In the next release (Wave 3 this spring) of PEswitch 900TX firmware,
we will have support for FDDI tree connections to the backplane.
Treeing 8 FDDI modules to the backplane requires only 14 channels
while dual ringing them requires 16. So if you tree the 8 PEswitch
900TXs with the next version of firmware, everything will work fine.
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