Just as a reference on Device/Bus speeds and bandwidth I found this website: http://www.acme.com/build_a_pc/bandwidth.html
A quick look over at it appears to be accurate. -David On Thu, 2004-12-09 at 10:55, Aaron S. Joyner wrote: > Brian Henning wrote: > > > ----- Original Message ----- From: "Christopher L Merrill" > > <[EMAIL PROTECTED]> > > > >> > >> "Gigabit Ethernet: This term does not connote an actual operating speed > >> of 1GB/sec. For high-speed transmission, connection to a Gigabit > >> Ethernet > >> server and network infrastructure is required." > >> > >> What does that mean? Does that mean I need something besides a switch > >> with a gigabit port? > > > > I think the description was trying to explain the maxim that a chain > > is only as strong as its weakest link... There are plenty of > > consumers (/idiots) out there that would not immediately grasp why > > they only get 10Mbit through their 10Mbit hub to their 10Mbit server > > when their workstation has 1Gbit. Dell's just trying (vainly, > > probably) to point out that you'll only get gigabit performance if all > > the steps along the way are gigabit. > > > > Cheers, > > ~B > > > Brian does a good job of pointing out the actual purpose of Dell's > statement, but there's a greater subtlety that bears mentioning. If you > use cheap hubs, and regular PCI Gigabit NICs, you won't see 1,000 Mbits > / second. In order to get up into that range, you're going to need to > overcome two bottlenecks. > > First the PCI bus can't really handle that much throughput, so you're > going to need to use something like Intel's CSA architecture (which ties > the Gig-E controller into the north bridge chipset, bypassing the PCI > bus), or go straight to PCI-X, preferably on a well-designed motherboard > using AMD's HyperTransport. > > Second, you'll also need to up the MTU of the interface and use what are > commonly referred to as "Jumbo Frames", meaning that you send data in > packets larger than the standard 1500 byte chunks. The maximum > practical MTU for Gig-E is usually 9000 bytes, but take note that most > inexpensive Gig-E switches won't support the larger frame sizes (and > will drop or truncate those packets). > > Hopefully this will help someone who's looking into Gig-E understand how > to set their expectations accordingly. :) > > Aaron S. Joyner -- David A. Cafaro dac(at)cafaro.net Admin to User: "You did what!?!?!" -- TriLUG mailing list : http://www.trilug.org/mailman/listinfo/trilug TriLUG Organizational FAQ : http://trilug.org/faq/ TriLUG Member Services FAQ : http://members.trilug.org/services_faq/ TriLUG PGP Keyring : http://trilug.org/~chrish/trilug.asc
