Radman said:
You can NOT just run a standard ether cable to your
comp. I know that because I tried. However, this is just a basic rule of networking. You would have to use a
crossover patch cable or run it to a
router or
hub then to the
comp. Then from the
hub you could also run it to the dimmers, if
ETC, and even to a wireless access
point. Then you can hook up nodes too, wired or if you have the wireless stuff, wireless using WiFi like 802.11 a/b/g whatever you use.
Well, no not exactly. We need to examine how the signaling between a
hub/
switch and an end device works on standard
utp cabling in order to understand this.
There are transmit and receive pins on your PC and the
hub/
switch/
etc. This is standard numbering, that is, pin 2 on your PC corresponds to pin 2 on your
hub and so on. So, if pin 2 is the transmit pin, and you have a straight
thru cable, then the transmit pin is corresponding to the transmit pin as opposed to the transmit pin on one end corresponding to the receive pin on the other end. This is where we need hte
crossover cable - the conductors in the cable are laid out in reverse on either end. A
hub/
switch actually internally reverses the transmit/receive pin numberings so that you do not need a cross-over cable from your PC to the
hub/
switch. Instead we use a straight
thru cable.
If you need to connect two PCs directly (or a
console ot a PC for example), we need a
crossover cable in order to get T & R corresponding with T & R at hte other end. The same goes for two hubs, switches,
etc.
Many hubs have a little hardware
switch you can push labeled uplink or mdi/mdi-x and it will electrically reverse the pinouts on teh port so you can connect two hubs/switches/
etc together. Newer Cisco switching gear has a software option to make a port an mdix port and thus an uplink port. In practice usually we just use a cross over cable.
It's also worth noting that you'll usually find fiber optic uplink ports on switches to be SC connectors which is a type of
connector that is one per
strand so you can reverse which side they go into on one end. Otherwise with something like an LC or MTRJ
connector, you'e got a single molded piece that you can't flip on the other end.