On Sunday 18 April 2004 5:21 am, Jim Cunning wrote:
On Apr 18 at 3:43am, Let_Me_Be wrote:
What hardware do I need to buy? Would prefer to set up a wireless - but if it is not practical I can go the hardwire route. (My house is wired for telephone in every room and there are four pairs of wires in each box, but only one pair is being used for telephone service, do if worse comes to worst could I use some of those extra 6 wires?)
You need only 2 pairs for 100Mbit, I don't see any problems with using the same cable for both telephone and network. (I'm using 1 cable for 2 computers on each sides). Sure telephone does use other voltage, but it will simply run on other cable, and i'm sure that it won't interfere with the network much.
You CAN use one cable for both ethernet and telephone, but the cable must be Category 5 or more for 100 Mbit. You cannot use the ordinary telephone wiring in your house for ethernet, unless it is at least Cat5. Cat5 cable is usually wired using one of two standards called EIA/TIA 568A or EIA/TIA 568B. A Google search for either one will return lots of pages about them. Here is one: http://www.pera.net/Category_5_Document.htm
An ordinary Cat5 ethernet connector has 8 contacts (4 pair), but only contacts 1, 2, 3, and 6 are used for ethernet. Contacts 4, 5, 7, and 8 could be used for telephone. An interesting set of slides on UTP (unshielded twisted pair) wire can be found at:
http://boulder.noaa.gov/noc/Training/noframes/sectionIII/sld001.htm
Many other resources are available. Google can help....
Jim
Even then, some issues remain for the LAN at home. The context in which all you have brought applies is wiring of an office. In this case, the telephone system is a star layout and it has its own switch which effectively isolates the internal telephone network from the outside. So firstly, the domestic telephone system is a bus topology, because all phones pick up directly on the outside line. There is no place on such a network which can serve as a location for a hub for more than 2 wallplates. So secondly, being connected directly to many km of outside line, you need to think about lightning strike transfer potentials from strikes near either end of the route [even if the incoming route is entirely underground], and all of the other interference a long line can bring. Let_Me_Be says the telephone runs in another cable, but it is actually a different pair of wires in the same cable we are talking about. and CAT5 insulation is quite thin. I suppose it is cost benefit. If you think that the cost of replacing fried network hardware [ignoring the possible interference] is outweighed by the cost of not using the existing wiring, then that's the way to do it. While I might share CAT5 cable in an office, this is because the phone lines are not natively external. I wouldn't at home, because this does not apply. Vince