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Newbe CAT 5 cabling questions (x2)
aparkman Aug-27-00 03:08 AM
My new house is pre-wired with CAT 5 to most rooms and this is currently being used for phone connections.

At three locations I have PC's which I would like to network. I would then like to provide one of these with a high speed connection (DSL/Cable modem) and use it as a gateway to the internet.

The CAT 5 cables run to a punch down block in the garage, where the phone feed runs in at the LHS. As far as I can see there is daisy chaining of this down the left edge to provide phone lines to each cable at the right edge.

I am just starting to research this now so forgive the naivety of the following questions...

(1) Does the phone wiring conflict with the EIA/TIA 568A standard?

What I would like to do, if possible, is ensure all my wall outlets are wired such that it doesn't matter whether I plug a phone or network patch cable to in (although I think this is foolishly optimistic!)

If this is possible I would like to find something like a block with punch down connecters on the left edge connected to RJ45 ports on it's right edge.

I would then:

- remove all but the needed phone wires from the daisy chain on the LHS
- remove the existing CAT 5 cables from the RHS and punch the relevant pairs into the
  vacant connecters on the LHS
- use a patch cable from the RJ45 ports which replaced the RHS of the previous punch down
  block to a hub (which I have)

Is any of the above feasible?

(2) Alternate approach...

Just thinking through the above while typing, it occurs to me that I could easily live with an alternate approach.

If there was a conector block with punch down at the left and RJ45 at the RHS then I could:

- crimp RJ-45 on the end of each CAT 5 run from the rooms
- wire the LHS in the same daisy chain as the existing phone wiring
- plug in the room cables associated with phone points to the RHS of this new block
- plug in the room cables associated with network points directly to a hub

This looks far more straight forward and the only thing I have to do to reset a network point to allow a phone is simply remove the associate cable from the hub and re-insert to the phone block.

Only questions here is what is the name of the block with punch down at the left and RJ45 at the right (if one exists) and where would I buy one.

Just in closing I'd like to say how grateful I am for the quality of materials presented in the Howto/network/cable section of this site. The quality of the order of presentation, explanations and diagrams is simply awesome. I've been involved with the internet for a considerable time (7 years) and it just doesn't get much better than this.

Sincere thanks!

Andy Parkman

1. RE: Newbe CAT 5 cabling questions (x2)
lbyard Aug-28-00 12:24 PM
In response to message 0
Please forgive my ignorance, but what is an LHS? If it is a 110 block (http://www.unicomlink.com/wiring/110Block.html) and the wires are punched-down correctly for telephone and network operation, than the first requirement has been met. For 100 Mhz operation the pairs should not be untwisted for more than ½ inch. A 66 block (http://www.smarthome.com/8610.html), which is very common, is not rated for CAT 5/100 Mhz operation (I would try it anyway). The jacks should be rated for CAT 5 or CAT 5E as well. Inspect the wall jacks and see if they have been wired correctly. See http://duxcw.com/digest/Howto/network/cable/cable5.htm. Again, pairs should not be untwisted more than 1/2 inch. The 100BASET Ethernet uses pins 1, 2, 3, and 6. Pins three and six are connected by wires from the same pair. A regular two-wire telephone line uses pins use pins 4 and 5, the center pair in the jack (RJ-45 and RJ-11). Your contractor may have installed/punched-down four wires for the telephones. An RJ-11 plug (regular old telephone) modular plug will plug-in to the RJ-45 jack and pick-up those wires. In other words, if the wiring was done correctly, it should work. Larry

2. RE: Newbe CAT 5 cabling questions (x2)
aparkman Aug-29-00 04:37 AM
In response to message 1

Thanks for your help, I believe I am getting there slowly and I apologize for the confusion. In my posting I used LHS and RHS for "left hand side" and "right hand side" respectively.

I believe you are correct in your assumption that I have a simple 66 Connecting Block. It has 50 rows of 4 clips - looking from left right the first two clips and last two clips seem to be connected together as pairs. There is a metalic clip which bridges the 2nd. and 3rd. clips together.

At the left side there is a run of 8 unshielded, colour coded cables in a daisy chain conecting the top most row to the 9th., 17th. ... and the second row to the 10th., 18th. ... etc. etc. in blocks of 8.

I'm thinking that each group of 8 rows corresponds to the wires of a cable which in turn correspond to the pins in the RJ-45 wall outlets (all of mine are marked CAT 5).

To allow all rooms to share a common phone line it is appropriate for telephone pins 4 and 5 to be daisy chained in this fashion. However, I don't think pins 1, 2, 3, and 6 should be daisy chained in this way since they correspond to data signals.

Also, as I understand your advice, a 66 punchdown block may or may not support 100Mhz speed but would support 10Mhz.

Supposing I want to try out the network with the stuff I have at 10Mhz, just to see what beneifts it brings my network. In this case, in each successive group of 8 rows, I would disconnect the clip which bridges between rows 1, 2, 3, and 6 but leave the clip in place between the 4th. and 5th. rows.

Then, for each room that I wish to have as part of my network, in the corresponding 8 rows in the punchdown I would wire to an empty column of clips an extra CAT 5 cable . This extra cable would end in an RJ-45 plug and would be inserted directly into a hub.

Does this sound right?

To tidy the above approach I could use the product displayed at:


and wire in pins 1, 2, 3, and 6 from the room cables and the common 4 and 5 from the phones. Then a regular patch cable could be used to conect the vacant RJ-45 port in the patch panel to the HUB.

Any warmer?

Again thanks for the help,

3. RE: Newbe CAT 5 cabling questions (x2)
lbyard Aug-29-00 02:58 PM
In response to message 2
Andy, I like tidy things also… But I am a New England Yankee and my backgound is in Electrical Engineering... The fewer things you have in a network and the fewer connections you make getting from point A to point B, the fewer problems you will usually have, the fewer things you will have to contend when troubleshooting, and the cheaper it will be. For example, in my experience, it is better to drill a hole through a floor covered with wall-to-wall carpeting and push a CAT 5 cable through the hole from a home run in the basement, and directly connect it to a PC then it is to snake it through the wall and connect it to a wall jacket. Also, for small networks it is much better to make one hole in the wall, etc. where all of the cables go to the hub/switch and connect them directly to the hub/switch. Furthermore, I am not about to completely rewire and existing house/building when installing a network and put multiple jacks in every room including bathrooms and closets, as some “perfectionists (including myself) are naturally inclined to do in the pursuit of ultimate technical beauty and a finality that anticipates for every conceivable circumstance. Grit your teeth and except those “imperfections” which will cost less and work better. Memory of that sloppy looking wire through the floor will pass when furniture has been in place for a while…

I am presently wiring my imperfect, 24-year old house for three home offices (yes, one office for each one us who live in it) and thought I would use this opportunity to write-up part of it.

I would try just two of the wires/jacks and connect them directly to a hub/switch. Use solid core wire between the block and hub/switch. Stranded wire does not punch-down well at all. I would run all of the pairs not used by the telephone. Or, you could temporarily crossover (http://duxcw.com/digest/Howto/network/cable/cable5.htm) two cables at the block and connect two PCs directly together for testing. If you do not have a diagram of the wiring (you should have and the block/wires should be labeled), you can use a multi-meter or continuity tester to find out what goes where. If your house is under warrantee and the specs call for network wiring, I would call the contractor have he or she rewire the house correctly. Have the contractor use a network wiring tech, not a telephone tech or electrician (no insult intended). Larry

4. RE: Newbe CAT 5 cabling questions (x2)
aparkman Aug-30-00 04:21 AM
In response to message 3

I agree with your sentiments. The house was an inventory home and was already built when I bought it. Luckily for me it came pre-wired with CAT 5 to the outlets in each room (otherwise I wouldn't be inclined to take this on).

If I follow your advice regarding simplicity then perhaps I should remove all strands of the CAT 5 cable from the two desired network points and crimp onto these RJ-45 connectors as per wiring guidelines.

The run of cable to the room *simply* becomes a long CAT 5 cable with a CAT 5 socket at the room end and RJ-45 connector at at the garage end (i.e. wiring closet).

Thus my network diagram is:

| |
| |
| |
: |5|
ROOM | |
: RJ-45
: :
v v
-[ ]-[ ]-[ ]-[ ]-
| |
| H U B |

At this point I get feedback on the viability of my cables. Assuming the installer didn't violate any of the cabling guidelines regarding tension, placement etc. then I know the above will get my data networking up and running.

Only trouble with above is room A no longer has a phone line wired to it. This is undesirable in the short term since I will still need to use a modem from the current PC location. I have not yet sorted out a high speed connection and my intention is to get a cable modem/DSL connection on a third PC which would plug into the HUB and be the gateway to the internet.

So, now we get to my dilemma...

With the RJ-45 on the end that came from the room there's no way for me to re-connect to the punch down block.

So, in your opinion should I:

  1. Add a 12 port bank of wireable RJ-45 sockets and run an extra pair of cables from rows 4 and 5 of each group of 8 rows in the punch
    down block to pins 4 and 5 of each RJ-45 socket.

    Thus if I move a room cable from the hub to the RJ-45 bank it has voice but no data and vice-versa.

  2. For each room I want to also be part of my data network...

    • Cut off one end of a patch cable.
    • Splice this end to one of the empty columns of clips on the punch down in the 8 rows corresponding to that room.
    • Plug the RJ-45 end into the HUB

    But wouldn't this give me a problem? Surely since the left side of my punch down daisy chains rows 1-8 of each room to rows 1-8 of each other room, whenever room A sends a data signal on the transmit wire, doesn't the HUB also get fooled into seeing the same transmit signal from every other room?

I could really use your confirmation on my logic leading up to the above choices and then your clarification on which of the two choices is better. I can live with choice 1 but would hate to think that it was equally easy to wire this so that each room is both on the data network and has a phone line to it. It's your quantification of the *easiness* in which I could attain the latter goal which will allow me to decide between the options.

Thanks in advance,

BTW - I'm a Welshman from the UK living in Florida, so all of this is new to me!

5. RE: Newbe CAT 5 cabling questions (x2)
lbyard Aug-30-00 04:42 PM
In response to message 4
LAST EDITED ON Aug-30-00 AT 05:32 PM (GMT)

Sure, that would be easy… Just disconnect all but the two pairs used for the telephone of the two wires you want for the network and cross the pairs at the block. Note, you need a crossover connection at the block according the diagram in the link provided in my previous message, not a straight-thru connection. Remember not to untwist the wires more than 1/2 inch. A phenomenon known as near-end crosstalk may cause problems if the wires are untwisted for a distance longer than that. The telephone connections in those two rooms are easily implemented at the wall boxes by purchasing some new wall plates with cut-outs for two jacks and two RJ-11 jacks for the phones. A lot cheaper than a patch panel and hub, I would say.

I have met a few Welshman in my day—while living in Europe. All of them (the ones I knew) were interesting/fun people, insane, and liked, let’s say, more than average libation. Larry

6. RE: Newbe CAT 5 cabling questions (x2)
lbyard Aug-30-00 06:12 PM
In response to message 4
LAST EDITED ON Aug-30-00 AT 06:38 PM (GMT)

I should add that arguments have been made for not mixing voice and data on the same cable different pairs)--e.g., Trulove, James, LAN Wiring – An Illustrated Guide to Network Cabling, McGraw-Hill, 1997--but I’ll bet the arrangement described/evolved in our messages will work just fine. These arguments do not seem to strong ones and this experiment is cheap enough to implement to be worth a try. Larry

7. RE: Newbe CAT 5 cabling questions (x2)
drbob Sep-01-00 02:03 AM
In response to message 6
However you definately won't get 100Mhz operation from it due to inteference from the phone line pair - a ring signal sends 9 volts down the line.

8. RE: Newbe CAT 5 cabling questions (x2)
aparkman Sep-01-00 02:05 AM
In response to message 6

Thanks for the confirmation. If I can borrow a crimp tool for the weekend I'm going to go for it!

I'm edging toward keeping the voice and data separate. I'll remove the net points from the punch down and crimp on the RJ-45. They'll be straight (not crossover) connections because I have the hub already - but I do see your point, I could have done an inexpensive test with crossover between two room points.

For the time being I'll use short wires to wire a modular jack socket into the punch down so I can plug back into phone only connections with my RJ-45's.

Also, thank you for your kind considerations about my fellow countrymen. We are a small nation with tight knit communities (although these are unraveling quicker than I care for) and we certainly have our share of characters!

I recently saw Notting Hill (Hugh Grant, Julia Roberts) and particularly enjoyed the portrayal by Rhys Ifans (himself a Welshman) of "Spike". There's a little "Spike" in every Welshman and I think the world is better off (or at least more interesting) for it!

I'll keep you posted on my results.


9. RE: Newbe CAT 5 cabling questions (x2)
aparkman Sep-04-00 07:14 PM
In response to message 8

With thanks to all my network is now up and running and after all the planning it really was quite painless.

I decided to keep voice and data separate so removed all cabling from rooms where I do not need the phone and crimped RJ-45 on and from there they went straight to my hub.

To facilitate the one point where in the short term I want to switch back and for between data and voice lines, I wired into the patch panel a short cable with pins 4 and 5 connected to an 8 pin socket. I did this first so that I had voice services restored as soon as I crimped RJ-45 onto the cable for this location.

Thus with my above safety net intact I went ahead and crimped RJ-45 to the cables where I currently do not have a phone and may want a network point. If I want phone back to any of these I can use the one spare 8 port socket to restore it. If I ever need phone lines to more than one additional location I'll buy a 110/RJ-45 patch panel to replace the punch down block - by that time they'll probably be a lot lower priced

I've done some basic testing using 'ping', file sharing and 250Mb worth of file transfer all with no problem. If anyone can recommend a more detailed testing procedure I'd be quite keen to follow it to establish bandwidth and error rates.

Again thanks to all, especially Larry, for their advice and encouragement. I know I could have got there on my own but have no doubt that the ease in which the project was realized was 100% due to the information and best practices which were shared via this site.

I am extremely grateful.


10. RE: Newbe CAT 5 cabling questions (x2)
Ra Byn Sep-11-00 04:08 AM
In response to message 9
For those of you that are thinking about rewiring or adding new wire to newtork, there is a company called LEVITON Telcom @ www.levitontelcom.com that makes a product called QuickPort. They are basically replacement covers for wall sockets. If you want to have a RJ11,RJ45,Cable,& RCA plugs, all on the same jack, just buy a blank with 4 holes in it & buy the specific jacks. Pop them in & punch the wires & voila, screw the plate into the wall socket. I just finished a job & it worked out great.

ra byn james

11. RE: Newbe CAT 5 cabling questions (x2)
Ra Byn Sep-11-00 04:09 AM
In response to message 10
I forgot to mention that all of this stuff is available at Home Depot in the phone accessories area.

ra byn james

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