network wiring problem

[pcr]

Hi!

I think I have a pretty specific problem, so that's why I'm opening a new thread.

I'm trying to connect two computers (one located in the 1st and other in 3rd floor) with the router (in the 2nd floor). So basically, the distance between the router and the computers is around 15m-20m (60ft). I've made the CAT cables by myself, of course put the colored wires in correct order, but still I'm getting no connectivity on none of the ends. Both of the computers keep showing the ethernet cable is disconnected. The light on the ethernet port blinks in a cca. 10-second interval. For me it seems like the signal through the cable is poor (too long cable, interference, bad connections ?).

Then I got an idea to try with an ethernet switch connected to the computer-end of that cable, and connect the computer and the switch with a shorter cable. And the connection works! Tried on both computers!

The problem is I don't wanna use the switch unless it's really necessary. And of course, I will need 2 switches to do that, one before each computer.

So, any idea of what could be the reason?

 

[Blain]

Did you use a cable tester to test your connectors when you assembled them?
They take out all the mystery.

 

[Ichinisan]

I often have to chop the end off and re-terminate. Is it possible that some pairs were swapped and you made a crossover cable?

 

[ScottMac]

Hi!

I think I have a pretty specific problem, so that's why I'm opening a new thread.

I'm trying to connect two computers (one located in the 1st and other in 3rd floor) with the router (in the 2nd floor). So basically, the distance between the router and the computers is around 15m-20m (60ft). I've made the CAT cables by myself, of course put the colored wires in correct order, but still I'm getting no connectivity on none of the ends. Both of the computers keep showing the ethernet cable is disconnected. The light on the ethernet port blinks in a cca. 10-second interval. For me it seems like the signal through the cable is poor (too long cable, interference, bad connections ?).

Then I got an idea to try with an ethernet switch connected to the computer-end of that cable, and connect the computer and the switch with a shorter cable. And the connection works! Tried on both computers!

The problem is I don't wanna use the switch unless it's really necessary. And of course, I will need 2 switches to do that, one before each computer.

So, any idea of what could be the reason?

What was the "correct" order?

 

[Ichinisan]

What was the "correct" order?

There are 2 standards. Generally, you want a straight through cable and the order of the colors doesn't matter as long as it's the same order on each side.

 

[pcr]

There are 2 standards. Generally, you want a straight through cable and the order of the colors doesn't matter as long as it's the same order on each side.

Exactly. I did it following T568A standard, but whatever, I triple checked the color order on the pins on both ends, and it is the same! For both cables! And of course they are not crossover.

Do you think a switch could correct the problem of a mismatched twisted pair??

If I don't find a solution I'll really buy a cable tester, but that's the just the last solution ...

 

[Ichinisan]

Do you think a switch could correct the problem of a mismatched twisted pair??

I dunno. Maybe if it has some more-advanced auto sensing. Old switches used to have a dedicated uplink port with tx/rx lines crossed (or a crossover switch for that port). Newer ones should auto-sense, but I don't even know how that would work if the PCs and router are also auto-sensing.

I've had fittings that just didn't work right with the port on a particular NIC or router. Maybe that's what you're encountering here.

 

[ch33zw1z]

Cabling issue.

What type of heads and crimper are you using?

When making your own cables, best to test them with a cable tester. Otherwise, pick up some 100ft pre-fabs.

 

[paul878]

Check the RJ45 connector and make sure all the pins are crimp down.
I have seem some cheap connectors and crimp combination that just don't work.

 

[Blain]

If I don't find a solution I'll really buy a cable tester, but that's the just the last solution ...

If you even think about making your own cables you should buy a cable tester.
For less than $10 shipped, it's a no-brainer.

 

[ScottMac]

There are 2 standards. Generally, you want a straight through cable and the order of the colors doesn't matter as long as it's the same order on each side.

The order of the color is critical, that's why I asked.
There is also more to proper termination than just crimping on an end I.e , maintaining the twist to the termination point, pair exposure, and strain relief,
To name a couple of the many.

 

[imagoon]

If you even think about making your own cables you should buy a cable tester.
For less than $10 shipped, it's a no-brainer.

If you even think about making your own cables you should just buy the cable and save yourself the trouble.

 

[Blain]

If you even think about making your own cables you should just buy the cable and save yourself the trouble.

Some people running cable through walls and/or floors, run bulk cable and add the connectors once run.
It's difficult to run a 1/2" connector through a 1/4" hole.

 

[Ichinisan]

I'm pretty sure some connectors play better with my crimp tool than others.

My apartment floor is made of giant concrete slabs with gaps between them that are perfect for running network lines to different parts of the room. One gap passes under the wall, so I was able to run all the cords to a walk-in closet, where I put up a shelf with all my network equipment. With a connector, you can't fit a network cable through the gap under the wall. I had a significant amount of Cat5e cable on a roll, so it only made sense to make my own cables.

I only had a few connectors and knew I'd have to buy more. I terminated the first 3 cords and they worked with no problems. Bought more connectors at Lowe's and made a third cable. Had to re-terminate both ends TWICE to get the third cable to work.

My tester stopped working since the last time I used it (about 5 years ago)...even with a new battery.

 

[imagoon]

Some people running cable through walls and/or floors, run bulk cable and add the connectors once run.
It's difficult to run a 1/2" connector through a 1/4" hole.

Then they should properly terminate it to a keystone. Doing it incorrectly is still incorrect. If you are putting a mod end on a piece of cable, you have basically done it wrong from the start.

 

[Ichinisan]

Then they should properly terminate it to a keystone. Doing it incorrectly is still incorrect. If you are putting a mod end on a piece of cable, you have basically done it wrong from the start.

What do you mean? A keystone jack + jumper cable is more impedance. Why not just put the 8P8C connector on the end of the cord?

 

[Zargon]

What do you mean? A keystone jack + jumper cable is more impedance. Why not just put the 8P8C connector on the end of the cord?

because after you trip over it and damage the cable you have to rerun everything instead of replacing just the patch cable :whiste:

 

[imagoon]

What do you mean? A keystone jack + jumper cable is more impedance. Why not just put the 8P8C connector on the end of the cord?

Impedance isn't a problem. The spec allows for 100m of cable of which about 30 meters is stranded, the other 270m is solid core terminated to keystones / patch panels.

8P8C connectors on solid core is taking a stationary in wall, brittle cable and putting it in to a movement situation which = breakage. 8P8C on to stranded needs the proper connector, die, strain relief among others which most people don't have let alone the proper tools to crimp them correctly. The cheap $20 tool from the hardware store is not the correct tool for the job. Those are typically for solid core dataroom patches (T1, SDSL) and demarc interconnects. Not for home amateur cable building.

 

[ch33zw1z]

Good thing his runs are only 60 feet

edit: along the same topic. I'm not a big chain hardware store shopper, but I ended up in Home Depot recently and was rather impressed by how much they've stepped up their home networking selection. It used to be half a rack shoved in a back corner behind electrical, now it's two full racks in a easier to find location. Cat 5e and 6 heads, keystones, strain relief boots, and low voltage wall plates, just to name a few. $75 for 1000' feet of Cat 5e patch cable? not bad.

 

[imagoon]

Good thing his runs are only 60 feet

Yeah means doing it incorrectly is likely to work "somewhat enough" and give him years of difficult to diagnose issues like random slowness after someone vacuums because the vibration has shifted the poor connection just enough etc.

 

[ch33zw1z]

Yeah means doing it incorrectly is likely to work "somewhat enough" and give him years of difficult to diagnose issues like random slowness after someone vacuums because the vibration has shifted the poor connection just enough etc.

One could speculate, if so inclined. Of course, he could have years of trouble free service.

It's a learning process.

 

[imagoon]

One could speculate, if so inclined. Of course, he could have years of trouble free service.

It's a learning process.

When learning there is a lot of value about learning to do it right, the first time. After throwing cable for years, I learned that a mod end crimper is the least useful tool I had in my bag. The 110 punch however was worth its weight is gold.

 

[ch33zw1z]

When learning there is a lot of value about learning to do it right, the first time. After throwing cable for years, I learned that a mod end crimper is the least useful tool I had in my bag. The 110 punch however was worth its weight is gold.

There is also value in doing it wrong and failing. You still keep both around, don't you?

 

[imagoon]

There is also value in doing it wrong and failing. You still keep both around, don't you?

Yes, the RJ45 crimper is used a lot in the demarc. Never in the cable plant any more except for rare things like a T1 cross over or T1 wrap. Never in the Ethernet environment. It his been almost 8 years since I built and Ethernet cable. Then I realized that I could have just bought the cable for cheaper than all the parts cost.

 

[Ichinisan]

Impedance isn't a problem. The spec allows for 100m of cable of which about 30 meters is stranded, the other 270m is solid core terminated to keystones / patch panels.

8P8C connectors on solid core is taking a stationary in wall, brittle cable and putting it in to a movement situation which = breakage. 8P8C on to stranded needs the proper connector, die, strain relief among others which most people don't have let alone the proper tools to crimp them correctly. The cheap $20 tool from the hardware store is not the correct tool for the job. Those are typically for solid core dataroom patches (T1, SDSL) and demarc interconnects. Not for home amateur cable building.

Thanks. I'll have to double-check if the cable is stranded or solid. If I recall correctly, I think this was a mostly-used roll I picked up from Goodwill or something many years ago. These lines don't go in-wall, so they're basically just long jumpers coming off the router and going through grooves on the floor to get to my entertainment center and desktop PC. I shouldn't need anything designed for long runs.