The short answer is: use at least Cat5e because it's probably not going to cost you much more (if anything) over the older stuff, and then you are reasonably up-to-date regardless of what you want to use the wiring for in the future. The only thing I would recommend is that you try and get solid core (which should be used for inside wiring) not braided (which should only be used for patch cables).
As far as PoE, here's what one of my partners says about it: "PoE is nothing more than electricity. Since all cables ranging from CAT1 to CAT7 have conductors, and conductors pass electricity, conventional wisdom is that they can support PoE. "What conventional wisdom is not telling you is that the engineer who designed the cabling components (i.e. jacks, switches, cable) designed the components to carry the data signal with a certain amount of EMI acting upon the conductors being used. Adding PoE on the unused pairs may present additional EMI forces onto the conductors carrying the signal. These additional forces can disrupt the existing signal slowing throughput. "How much you ask? That is dependent upon: ---The dielectric constant of the insulation material used on the pairs that were intended not to be used. ---The frequency and amperage of the voltage being sent down the pairs being used for PoE. ---The distance of the horizontal link and channel. "As an example, in what is known as 4x4 construction of a cable, all 4 pairs of a cat5 cable use the same insulator for the conductors. In 4x2 construction (very prevalent when there is a shortage of Teflon, mid 90's was the last) the transmitting pairs use Teflon and the Jacket is Teflon, but the other two pairs of wires are usually PVC (as long as the Jacket is Teflon, the cable inner cables could be PVC and still meet the Plenum rating for the fire codes). The PVC is used to reduce manufacturing costs, but since PVC has a different dielectric constant it will perform differently from the other pairs within the cable." Thing is, a typical VoIP call will not need more than 100K of bandwidth, which is 1/100th of what is delivered on 10baseT, and 1/1000th of what 100baseT provides. The question is whether the loss is going to be experienced as packet loss (which would be bad), or bandwith loss (which the phone would hardly miss). I'd like to think that PoE should work over Cat3, but I have not yet heard a compelling argument either way. Jim > -----Original Message----- > From: Richard (Rogers @ work) [mailto:[EMAIL PROTECTED] > Sent: February 8, 2007 10:21 AM > To: [email protected] > Subject: [on-asterisk] Power over ethernet cable fro IP Phones > > Hi all, > > I am trying to install some network cable in my house ready > for POE IP phones in every room. > Would anyone knows if POE only works with CAT5 cable? > > I am just trying to make sure I install the right type of > cable for the POE phones I am going to buy later. > > Thanks, > Richard > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] For > additional commands, e-mail: [EMAIL PROTECTED] > > > > > > -- > No virus found in this incoming message. > Checked by AVG Free Edition. > Version: 7.1.411 / Virus Database: 268.17.30/674 - Release > Date: 07/02/2007 >
