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supercoquiFlag for United States of America

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Cable just doesnt seen to work.

Ok currently I am cabling a resort in puerto rico. Here is the setup:

DHCP SERVER ---(10 feet, CAT5)---- DLINK FAST ETHERNET SWITCH(#1) ----(200 feet(CAT5)-- NETGEAR SWITCH (#2) -----(100 feetCAT5)--- DLINK FAST ETHERNET SWITCH (#3) ----- (100 feet CAT5) ------ NETGEAR HUB 10/100Mbps


ok on the netgear hub i got connected 1 device and it works fine, that device is at about 50 feet distance.
I can connect other computers and switch ports and it all works fine.
The problem lies when i try to run a 120 feet cat5e wire. It doesnt get signal, for some weird reason. I tried using a cable tester that check continuity on all 8 wires and they are setup fine and look fine(no shorts and no broken wires). I have the equipment connected to a normal port and the wires are straight thru(no crossover or patch, all wires straight).

I also played around changing the ports and they all work fine. I am starting to believe that it has to be the length, but isnt CAT5 rated for 100 meters (328 feet)?? I am using the same laptop to test all cables, so the laptop is configured right.

Is there any other test I need to do to the wire?? I would believe continuity is enough because it is just 8 copper pairs. I only untwisted 1/2-3/4 inch of the wires pairs so i could put it on the RJ45 connectors, so basically the wires are made to specs. I replaced the jack multiple times and cut some more wire just to make sure it wasnt the jacks or parts of the ends of the wires.

I am really lost here, maybe there is something I am not seeing. Been checking this all day and need to have it fixed before friday. Throwing the wire again is the last option because it has been a pain to pass the wires thru a lot of pvc pipping slowly as to not break it and it took over 6 hours to get it in(2 pairs witha phone line going thru a 1/2 inch pvc pipe.


Forgot to mention that wireless is not an option as we are running a system called MICROS for restaurant and hotels and it doesnt like wireless at all. The latency caused by wireless is a no no for micros.
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ISoul
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Take a quick read through this thread: http://episteme.arstechnica.com/6/ubb.x?a=tpc&s=50009562&f=469092836&m=5760980942

While CAT5 is usually rated for 100m total, the more splits there are, the more reduced the distance will be.
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Atnex

I would recommend running some ping tests from the last known good devices in the chain and see what sort of latency you are getting.
Also verify you have the cable wired correctly for straight through or cross-over.
If I were doing it I would go with either ethenet extender devices, or prepatched fiber and required media converters.

www.blackbox.com

Are we correct in assuming that this series of hubs is to extend the cable. Indeed latancy is an issue when the total distance is greater than 100 meters including repeaters.
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ok verified and remade the plugs. They check correctly for straight through. It came to my mind that it might be losing signal, so i decided to isolate that part of the network.

I only placed two laptops with static ip addresses, a switch, a short wire and the long wire. Connected laptop#1 to the short wire, and laptop#2 to the middle wire that is known to be good. The ping worked between the laptops. I went ahead and then connected laptop#1 to the long wire which is the one having problems. It was able to connect to the switch. I tried pinging laptop#2 but the request keep on timing out, i increased the time of the ping and no luck. Something i did noticed is that sometimes I connect either laptop#2 or laptop #1 to the long wire and I get limited connectivity.

Right now the switch looks like this

_____________
                      |
S                  1 ----------------short wire(5ft)-------- laptop#2 (192.168.0.101-STATIC IP)
W                   |
 I                  2-----------------middle wire (50ft)------laptop#1 (192.168.0.195-STATIC IP)
T                    |
C                 3-------------------------LONG WIRE THAT IS BAD (120ft)---------------
H                    |
                   4  
_____________|

Pinging is good. laptop #2 ping 192.168.0.195 with 1ms.

_____________
                      |
S                  1 ----------------short wire (5ft)--------
W                   |
 I                  2-----------------middle wire (50 ft)------laptop#1 (192.168.0.195-STATIC IP)
T                    |
C                 3-------------------------LONG WIRE THAT IS BAD (120 ft)---------laptop#2 (192.168.0.101-STATIC IP)
H                    |
                   4  
_____________|

Ping to 192.168.0.195 gives request timed out. I am starting to think that the wire is bad, even tho the cable tester gives me continuity in all 8 wires. 5 cat5 wires where passed thru a 3/4 inch PVC pipe and I am starting to think that even tho we made sure that wire wouldnt get twisted one of the curves broke it. Even tho it has continuity in all wires and they dont short, there must be something else wrong in that wire.

Anyone has any experience with bad CAT5e wires??? Will some bending make it go bad. That is the part that is getting to me, the wires read continuity but they can only register to a switch they cannot trasmit or ping anything.    
I would check to make sure the connecers are put on the cable correctly.  If the wires are in the wrong order you may get conectivity on each wire but the signal will be gretly reduced over distance.  Incorectly wired cables will work over short distances, but not over long distance.

If your cables are wired correctly you should be OK for up to 100M between devices, if you need longer runs get repeaters or fiber.

Check out this link
http://www.lanshack.com/make-cat5e.aspx


eb
On the long cable, you most likely need one end to be straight through and the other end to be cross-over.  This is usually the case with two switches that do not auto sense for cross-over.
According to his picture he's also attaching a laptop to the long wire, the laptop would not need a crosover.  If is switch to switch then yes a crosover may be needed.

eb
hmm looking at that tutorial it. I tho that as long as the wires are on the same order on both ends it should be a good working straight thru cable, tomorrow when they open the store i will go and get some more RJ-45 conectors (ran out this morning). The way i have it is:
(TOP VIEW)
______________
                        |-BROWN/WHITE
________          |-BROWN
             |         |-GREEN/WHITE
             |         |-GREEN
             |         |-ORANGE/WHITE
_______ |         |-ORANGE
                        |-BLUE/WHITE
______________|-BLUE

Both jacks look the same from the top.  Was setting the up like this part of the problem? Tomorrow i will make them to   568-B standard.

Basically my cable tester send an electrical signal in order form pin 1 to pin 8, one pin at a time. So if i get the same order in the remote unit I knew that the cable was wired as a straight one.
The way you have it you don't have the correct twists.  The twists provide a kind of shield that allows the signal to travel further.  Your scheem will work on short runs but not long ones.

Good luck

eb
Great! keep us posted.

here is another good link  http://yoda.uvi.edu/InfoTech/rj45.htm#straight
I will cut them like that.... to test them with my laptop to make sure it works fine.

568B Wiring
__________
                 |-ORANGE/WHITE
LOWER       |-ORANGE
PART         |-GREEN/WHITE
OF             |-BLUE
PLUG          |-BLUE/WHITE
                 |-GREEN
                 |-BROWN/WHITE
__________|-BROWN
         

So them if I wish to connect hub to hub, how would I make the wire crossover. One of my hubs tends to make all the ports crossover if i press the uplink button, so I am going to just have it like normal.
Correct, if you have an uplink port on one of your switche/hubs, you can use the uplink port with the button enabled.  With this configuration, you can leave the cable straight through.
If the stright cable does not work here are the instructions for a crosover http://www.littlewhitedog.com/content-8.html

eb
Take the PC that won't connect and place it where another PC does connect. If it connects there then you need to run a new cable...you might want to run it along the ground and not though all the various conduits. If it connects then run DUCT tape it to the cable that doesn't work and YANK it though...!!!!!  DONE DEAL.
hi, there

what kind of switch is it you have in place there ??? Cisco

When you insert the cable on the switch does it light up ? Green orange or else from that specific connection. ?

If this is a manageable switch try under the CAM "MAC address table if you ping its own IP" see if it is in the address table.......

Cooledit
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ok, they will bring me new jacks today in the afternoon.
@Atnex The hubs I will be using I am reusing old ones, 4 ports work but I am not sure the uplink one works.
@ebjers thanks for the address, it will come in handy.
@Computerguy107 i switched the wire to other ports and no luck. It must be the twist eb mentioned.

 @cooledit the switch is a DLINK fast ethernet as the whole network runs fast ethernet. The lights do light green and flash as if they where receiving. The laptop doest get connected and sometimes It gets limited conectivity. The configuration is correct on the laptop as it connects to the shorter wires.
Allright guys, it was indeed the order of the wires when it was terminated. I redo it in the 568B order and it worked wonderfully. I spend yesterday and today doing all the terminations on the wires and the bar is getting signal now. Also I am getting pings to the server now of 1ms where I was getting 10ms, which is really nice. Thanks a lot for the information.
 
Glad you got it working