🚀 go-pugleaf

In article <33IrKTAjuoA40ANQ@oxim.demon.co.uk>, Mark Booth
<markbFrom2@oxim.co.uk> writes
>In article <KdtUJGAx0x83EwVT@ch-w.demon.co.uk>, John Chapple <jc@ch-
>w.demon.co.uk> writes
>>The disadvantage of the dual speed hubs is that _everyone_ either runs
>>at 10baseT or 100baseT, depending on the settings on the cards (as
>>well).
>
>Most of the dual speed hubs I have seen do not work like this.
>
>What I recognise by a dual speed hub is a hub where each port can be
>either 10 or 100. Internally all of the 10baseT ports are a logical hub,
>and all of the 100baseT ports are logically a hub. These two logical
>hubs are connected by a two port switch (10 on one side, 100 on the
>other). The total bandwidth of the hub is thus 110Mbps (10+100).

Well, this old two speed hub must be the exception, or more basic than
most (nowadays) then. If any of the cards are 10BaseT, then they can
only communicate with other 10BaseT cards, not with the 100BaseT cards
at all.

>If you have a mixture of 10baseT and 10/100baseT cards in your PCs you
>should get quite an improvement over just having a 10baseT hubs.

Yes, if mine worked the way the ones you've looked at do. :-(

>
>I almost went for dual speed hubs, but the price difference to a fully
>switched system was relatively small given the boost in performance, so
>I decided to go the switched route.
>
>>The real answer is a fully switched 100BaseT/10BaseT hub
>
>When I replaced our network, I went for a top tier N-way 100baseT switch
>which connected all of the second tier switches with all of the servers.
>The second tier had 2+8 switches (2x100baseT ports and 8x10baseT ports).
>One of the 100baseT ports was used for the up-link to the top tier
>switch, one for the machine that needed the most bandwidth. The rest of
>the machines were placed on the 10baseT ports.
>
>Going for this structure was far cheaper than trying to have switched
>10/100baseT throughout, and also meant that few machines needed to have
>their network cards changed. About half of our machines have new enough
>network cards to do full duplex, and I still have our old shared hub to
>swap in if anything breaks.

I suppose, on a large working network, the cards could be a major
expense (as well) & of course it makes sense to share bandwidth
prudently, when most users themselves would not be using the full
bandwidth in the normal course of events.

There are so called dual speed hubs from under 100ukp to over 399plus!
for eight ports. It all depends on how a two speed hub is defined.
Having looked carefully at the spec of the >100ukp it worked in the way
I described, more expensive models featuring (for instance)
'autosensing' seem to work in the way you describe

-- 
John Chapple