Ryda85
MIS
- Jun 18, 2009
- 4
Just wondering if any of you still use cat3 for voice aplications.
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Cat3 useless?
- Thread starter Ryda85
- Start date
- Status
Infinity306
IS-IT--Management
but then you all knew what i was talking about and just wanted to smart off..
Infinity306
IS-IT--Management
@syquest
"RJ11 has nothing to do with CATEGORY OR DATA ANYTHING!!!
It is a wiring arrangement for tip/ring dialtone for 6-position MODULAR JACKS, specified in FCC Part 68.
....JIM...."
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Right on.. so why use anything above Cat 3 for Voice cable?
"RJ11 has nothing to do with CATEGORY OR DATA ANYTHING!!!
It is a wiring arrangement for tip/ring dialtone for 6-position MODULAR JACKS, specified in FCC Part 68.
....JIM...."
-----------------------------------------------------------
Right on.. so why use anything above Cat 3 for Voice cable?
One point that is being missed in this discussion is the whole notion of structured cabling. The EIA/TIA specs last I looked (10 plus years ago) specified two Cat 5 cables to each drop location. This allowed for the use of Voice, Data and Video.
Cat 5 specs allow for data transmission up to 125 Mhz, and 100m ethernet runs at 80% of 125mhz, so it runs at the ragged edge of the cable. If you run ethernet over Cat 3, which is perfectly acceptable, you will only get 10m ethernet.
The whole idea on Cat 6 is to extend the limited distance that 100m ethernet can run over cat 5, which is less that 100 meters.
I could be wrong on some of the facts I'm pulling from the old grey matter, but you get the gist of it.
So, voice over Cat 3, works perfect, I would use it today with no hesitation. But, if I'm wiring my business today, I would not short change myself by running Cat 3 in place of a Cat 5 drop, as the cost of labor to replace that drop far outways the cost to put it in the first time.
If I'm running a short cable in an equipment room for voice, I'll use whatever is handiest, as cat 5 has no appreciable benefit to Cat 3.
With VOIP, and the need for QOS, the need for that second cable to be CAT 5 starts to diminish, and the CAT 3 can actually make some sense.
BTW, as long as we are being coy with each other, that picture of the telephone cable with the clear tip on it is not technically an RJ11 cable. It does only have two connectors on it, as you can see. However, a true RJ11 cable, per the standards, has a blue tip on it, which defines it as a single pair, and an RJ11. an RJ14 has an orange tip and 4 conductors. We've lost our way over the years and accept lower cost goods that no longer meet the Standards. Its no different with CAT 3 and CAT 5, we use them to meet business needs, many times ignoring standards. Which allows us to debate their usage for 4-5 pages on this thread.
It's all terminology, that we mix and match to meet our communications requirements, but much of it is not fully understood, nor interpreted correctly. EIT-TIA standards can be a source of determining where the rubber meets the road so that everyone speaks the same language.
Sounds like a good subject for the geezer section on PBX2SIP.com
Cat 5 specs allow for data transmission up to 125 Mhz, and 100m ethernet runs at 80% of 125mhz, so it runs at the ragged edge of the cable. If you run ethernet over Cat 3, which is perfectly acceptable, you will only get 10m ethernet.
The whole idea on Cat 6 is to extend the limited distance that 100m ethernet can run over cat 5, which is less that 100 meters.
I could be wrong on some of the facts I'm pulling from the old grey matter, but you get the gist of it.
So, voice over Cat 3, works perfect, I would use it today with no hesitation. But, if I'm wiring my business today, I would not short change myself by running Cat 3 in place of a Cat 5 drop, as the cost of labor to replace that drop far outways the cost to put it in the first time.
If I'm running a short cable in an equipment room for voice, I'll use whatever is handiest, as cat 5 has no appreciable benefit to Cat 3.
With VOIP, and the need for QOS, the need for that second cable to be CAT 5 starts to diminish, and the CAT 3 can actually make some sense.
BTW, as long as we are being coy with each other, that picture of the telephone cable with the clear tip on it is not technically an RJ11 cable. It does only have two connectors on it, as you can see. However, a true RJ11 cable, per the standards, has a blue tip on it, which defines it as a single pair, and an RJ11. an RJ14 has an orange tip and 4 conductors. We've lost our way over the years and accept lower cost goods that no longer meet the Standards. Its no different with CAT 3 and CAT 5, we use them to meet business needs, many times ignoring standards. Which allows us to debate their usage for 4-5 pages on this thread.
It's all terminology, that we mix and match to meet our communications requirements, but much of it is not fully understood, nor interpreted correctly. EIT-TIA standards can be a source of determining where the rubber meets the road so that everyone speaks the same language.
Sounds like a good subject for the geezer section on PBX2SIP.com
RJ ANYTHING has nothing to do with cable! It is an abbreviation for REGISTERED JACK!! Do you see cable anywhere?
Yea, it's terminology all right, and it becomes meaningless and confusing, when bastardized and used incorrectly!!
....JIM....
Yea, it's terminology all right, and it becomes meaningless and confusing, when bastardized and used incorrectly!!
....JIM....
pbx2sip, don't confuse the color code with the color of the connectors on the ends of base cords. Flat base cords have 2,4,6 or 8 wires in them, and since they are not paired they are in the colors of Green, Red, Black, Yellow, White, Blue, Orange, Brown. You pick the colors for lines 1-4 based on the number of wires in the cable, or they may be all the same color, a PITA if you're making a long cord because you either have to hope there's a ridge in the cordage, or run your thumb and finger down the length of the cable so you can keep the tabs down to reverse the wires.
Panasonic happens to use Green plastic for their 6p4c plugs, and someone like AT&T...Comspec?..uses blue plastic for something, but, all we ever use and buy is clear.
LkEErie
Panasonic happens to use Green plastic for their 6p4c plugs, and someone like AT&T...Comspec?..uses blue plastic for something, but, all we ever use and buy is clear.
LkEErie
We run three Cat5 cables for each drop. Two for Data. But we split the one for voice. BL and OR pairs to jack A. GR and BR pairs to jack B. Two phones on one cable. Then a splitter can be used on each jack to utilize all four pairs in the cable if necessary (that happened once in the past eight yrs).
>****
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In the early days of the RJ standards, phones actually shipped with color coded tips on their cords - blue had two connectors in them on pins 3&4, and a two conductor cord. There was also a 4 conductor cord, with 4 pins on 2-5 and an orange tip on them. A six conductor cord had a green tip on it. In later years they went to the clear color tip. That color scheme is defined in the standards, and you do run across cables like that now and then.
Syquest, your right, the RJ11 cable we commonly refer to has nothing to do with the RJ standards, any more than the tip or the jack itself, since RJ specifies the actually wiring specification. It's use has been bastardized for for about 3 decades now, hard to change what is generally accepted practices, even if they aren't correct.
Syquest, your right, the RJ11 cable we commonly refer to has nothing to do with the RJ standards, any more than the tip or the jack itself, since RJ specifies the actually wiring specification. It's use has been bastardized for for about 3 decades now, hard to change what is generally accepted practices, even if they aren't correct.
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