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Hi Grant On 13/03/07, Grant Sewell <dcglug@xxxxxxxxxxxx> wrote: > On Sat, 10 Mar 2007 15:07:41 +0000 > "Richard Brown" wrote: > > > Does it make a difference depending on connection speeds. There is a > > difference between a hub and a switch. What speeds are your network > > cards as well? 10/100 I wouldn't worry but if you have a 1000 then it > > could make a difference. Just thought I would add these thoughts and I > > don't suppose with two computers networked together it makes a whole > > lot of difference. > > As a point of interest (well, to me)... you *cannot* have a gigabit > ethernet hub. Gigabit over copper *must* use switches. 10mbps and > 100mbps both support "half duplex" (why it's not called simplex, I do > not know) communication where they can either talk, or listen, but do > both simultaneously. For "full duplex" communication, the network > devices are both talking and listening simultaneously, so in effect a > 100mbps connection running at full duplex actually provides you with > 200mbps bidirectional throughput. Gigabit ethernet, however, *must* > operate at full duplex in order to reach the magic 1000mbps speed. > Indeed, where-as on 10/100 networks using Cat5(e) only 2 pairs of > cables are used, with 1000mbps networks all 4 pairs are being used > simultaneously, in both directions. Each pair of cables on Cat5e has a > (current) maximum potential throughput of 125mbps (apparently); 4 pairs > of cables @ 125mbps/pair = 500mbps; 500mbps in both directions > simultaneously = 1000mbps. Hubs do not support full duplex, > whereas switches do; gigabit must use full duplex therefore gigabit > cannot use hubs. > Thanks for pointing that out. Maybe you could add a further enlightenment please? What is the difference between managed and unmanaged switches (besides the spelling!). Thanks. -- Rich http://www.cregy.co.uk Embracing what God does for you is the best thing you can do for him. Romans 12 v 1 -- The Mailing List for the Devon & Cornwall LUG http://mailman.dclug.org.uk/listinfo/list FAQ: http://www.dcglug.org.uk/linux_adm/list-faq.html