On Mon, 8 Oct 2001, Paul Lussier wrote: >> You also need equipment capable of handling it. In particular, you cannot >> do FDX with a repeater. You need a switch. > > Correct, though, is there anything actually prohibiting a repeater from > using FDX, or is it simply that the manufacturers wish to keep things > simlpe and therefore cheap?
It is inherent in the way a repeater works. #ifdef GORY_DETAILS A repeater is a simple device. A signal comes in one port, and is regenerated on the other port(s). No intelligence or buffering is involved. A 10BASE-T network (technically, "collision domain") is logically equivalent to a 10BASE-5 network with thick yellow cables and vampire clamps. All the nodes are on the same bus, and when one node transmits, they all see it. Because all nodes on a repeater are on the same bus, full duplex is not possible, for the same reason that only one person at a time can talk on a two-radio. A switch is basically a specialized computer with a bunch of network interfaces. A packet comes in one port and is buffered in memory. The switch decides where the packet is going and sends it out the appropriate port(s) (if any). Each port is a separate Ethernet collision domain, bridged to all the others (a switch could be accurately termed a "multi-port bridge"). A collision on one port only affects that port (collision domain). 10BASE-T uses separate pairs for transmit and receive. If two nodes are directly connected (as is the case with a switch), there is an isolated channel in each direction. If both ends support it, they can switch to a full-duplex mode, and both can transmit at the same time, without fear of a collision. Full-duplex mode basically changes your Ethernet bus into a point-to-point network. #endif /* GORY_DETAILS */ > If you want quality, you must be willing to pay for it (OSes excluded ;) Software included. There are other methods of payment besides money. With Free Software, you pay it forward, instead of paying it back. :-) -- Ben Scott <[EMAIL PROTECTED]> | The opinions expressed in this message are those of the author and do not | | necessarily represent the views or policy of any other person, entity or | | organization. All information is provided without warranty of any kind. | ********************************************************** To unsubscribe from this list, send mail to [EMAIL PROTECTED] with the following text in the *body* (*not* the subject line) of the letter: unsubscribe gnhlug **********************************************************
