Q: I have just been handed a serious setback by my data cabling company. A few years ago, while wiring our dorms for phones, we installed a 6-pair Category 3 cable to each residence room. One pair is used for analog telephones.
Representatives of my data cabling company, which just completed wiring two classroom and office buildings and our library, inform me that it is not a good idea to run data in the same cable as analog voice. They do not like the idea of running data over the same cable as digital voice, either.
Therefore, instead of just installing hubs and connecting both ends for a 10Base-T Ethernet network, they say we need to pull separate cable for data, which drives the cost up significantly.
Are they correct about not mixing data and voice in the same cable, using different pairs for each? Can we not mix digital voice and data in different pairs within the same cable, either?
Robert Agnew
Beaver College
Glenside, PA
A: TIA/EIA-568A, Annex D.1, recommends that the user consult with equipment manufacturers, applications standards (in this case IEEE 802.3) and system providers for shared sheath guidelines for multipair unshielded twisted-pair cables. Since multipair is defined as anything over 4-pair cable, I suggest that you contact 10Base-T equipment manufacturers until you find one that will work on your cabling arrangement. Most will. However, this will not likely be the case for speeds beyond 10 Mbits/sec.