Had.an Ethernet cable degrade from 1gbps to 100mbps on me for the first time.

[Beershaun]

I thought I'd share this since it was the first time I've experienced it and I thought it was strange.

I recently had a 3ft Ethernet cable go bad on me causing my connection to drop from 1gbps to 100mbps between my main home network switch and a small local "smart hub" in my home office.

It was connected from my office hub to my wall cat6 keystone jack.

The cable was a decent quality cable that had been working fine for 5 years and then one day it just dropped down to 100mbps connection. Nothing outwardly wrong looking about it.

Once I put in another cable I had lying around the connection was back to 1gbps.

Just a lesson I'd share that decent cables can sometimes just degrade for no apparent reason and always try swapping them if you run into wierd issues.

 

[DonH56]

I thought I'd share this since it was the first time I've experienced it and I thought it was strange.

I recently had a 3ft Ethernet cable go bad on me causing my connection to drop from 1gbps to 100mbps between my main home network switch and a small local "smart hub" in my home office.

It was connected from my office hub to my wall cat6 keystone jack.

The cable was a decent quality cable that had been working fine for 5 years and then one day it just dropped down to 100mbps connection. Nothing outwardly wrong looking about it.

Once I put in another cable I had lying around the connection was back to 1gbps.

Just a lesson I'd share that decent cables can sometimes just degrade for no apparent reason and always try swapping them if you run into wierd issues.

When I have seen a network cable degrade like that it was because of a broken wire, like a ground or (more likely) one side of the dif pair broke (went open). Good catch!

 

[GD Fan]

Maybe try cable risers next time...? I hear carpet can be hell and we all know about hardwood floors!

 

[sam_adams]

 

[JSmith]

The cable was a decent quality cable that had been working fine for 5 years and then one day it just dropped down to 100mbps connection. Nothing outwardly wrong looking about it.

After while of being plugged in and gravity, the contacts can become out of contact and the cable stops working. Often just squeezing the connector will fix it for a while.

The contacts can also develop surface oxidisation over time or dry dust build up, so cleaning same may also rectify the problem.


JSmith

 

[restorer-john]

What @DonH56 said.

Get yourself a cable tester- they are as cheap as chips and test all the pairs sequentially either locally or remotely.

https://www.aliexpress.com/item/32673219952.html?spm=a2g0o.productlist.main.3.501359e2vPaw4F&algo_pvid=2b5eda80-a81d-488b-865f-76a0e61f2488&algo_exp_id=2b5eda80-a81d-488b-865f-76a0e61f2488-1&pdp_npi=4%40dis%21AUD%216.01%214.75%21%21%213.83%21%21%402101e9d316928486633771768e35cf%2160112274569%21sea%21AU%213522927307%21&curPageLogUid=jTz3hIui2ziq

Or better still, get one of these. You can test a huge range of leads for connection/shorting/OC, even speakon 4P and 8P, TRS, XLRS/DINS RCAs etc. And a cool continuity tester. Beats messing around with a DMM trying to push probes into/onto round recessed pins.

That unit above is about AU$70, made of metal and is as tough as a brick.

Here is my unit, I've had this for about 10years and it sits always within easy reach.

Honestly, just get one. The reduction in profanities you will utter when you don't have to deal with slipping test probes is worth it. When someone asks you to check why their system has a hum or a channel has dropped out- you can quickly test all the leads- no matter the combinations. Throw an RCA to BNC adaptor on the side to check BNCs.

 

[Beershaun]

Thanks for all the responses and feedback! I'll check out a cable tester. Cables, they may not need to be expensive, but they definitely can go bad!

 

[Mnyb]

Or the contacts sometimes just reconnecting the same cable can make it work again .
Then you get another one anyway or make new connectors .

OT flukes instrument probe cables are very prone to developing faults , this is infuriating when trouble shooting

I’ve learned to alway cut a broken cable in half and throw it in the bin , otherwise some other sucker at the site will reuse it ( or you two weeks later ).
Similar to not put broken pens back into the drawer...

 

[wwenze]

At least it degraded cleanly... my new wall socket auto-negotiates a 1Gbps, but it never works unless I force it to 100Mbps

Thanks for all the responses and feedback! I'll check out a cable tester. Cables, they may not need to be expensive, but they definitely can go bad!

If you have a Realtek, this is a free download:

Download Realtek Ethernet Diagnostic Utility 2.0.8.0

Download Realtek Ethernet Diagnostic Utility 2 Realtek is official tool to diagnose ethernet problems on many of their network cards

en.taiwebs.com

 

[MaxwellsEq]

What @DonH56 said.

Get yourself a cable tester- they are as cheap as chips and test all the pairs sequentially either locally or remotely.

View attachment 307565

https://www.aliexpress.com/item/32673219952.html?spm=a2g0o.productlist.main.3.501359e2vPaw4F&algo_pvid=2b5eda80-a81d-488b-865f-76a0e61f2488&algo_exp_id=2b5eda80-a81d-488b-865f-76a0e61f2488-1&pdp_npi=4%40dis%21AUD%216.01%214.75%21%21%213.83%21%21%402101e9d316928486633771768e35cf%2160112274569%21sea%21AU%213522927307%21&curPageLogUid=jTz3hIui2ziq

Or better still, get one of these. You can test a huge range of leads for connection/shorting/OC, even speakon 4P and 8P, TRS, XLRS/DINS RCAs etc. And a cool continuity tester. Beats messing around with a DMM trying to push probes into/onto round recessed pins.

View attachment 307567

That unit above is about AU$70, made of metal and is as tough as a brick.

Here is my unit, I've had this for about 10years and it sits always within easy reach.

View attachment 307568View attachment 307569View attachment 307570

Honestly, just get one. The reduction in profanities you will utter when you don't have to deal with slipping test probes is worth it. When someone asks you to check why their system has a hum or a channel has dropped out- you can quickly test all the leads- no matter the combinations. Throw an RCA to BNC adaptor on the side to check BNCs.

Who tests the cable testers?

 

[MaxwellsEq]

I thought I'd share this since it was the first time I've experienced it and I thought it was strange.

I recently had a 3ft Ethernet cable go bad on me causing my connection to drop from 1gbps to 100mbps between my main home network switch and a small local "smart hub" in my home office.

It was connected from my office hub to my wall cat6 keystone jack.

The cable was a decent quality cable that had been working fine for 5 years and then one day it just dropped down to 100mbps connection. Nothing outwardly wrong looking about it.

Once I put in another cable I had lying around the connection was back to 1gbps.

Just a lesson I'd share that decent cables can sometimes just degrade for no apparent reason and always try swapping them if you run into wierd issues.

Ethernet patch cables do fail. On a huge office site with thousands of patch cables, there will be a steady trickle. A lot of it is just wear and tear, but sometimes a crimp connection is not manufactured perfectly and later fails probably due to contamination of the junctions.

My first big network was 10Base2 with coax, BNCs and terminators. This was very susceptible to minor cable issues. 10BaseT was a joy in comparison.

 

[FrantzM]

Hi

I am in IT, and have been doing structured cabling for quite a while... a bit over 25 years.. This kind of things do happen. The reality is that Ethernet even at 1 Gbps can work on anything , even barbed wires... Yes. And many home applications do not need that kind of bandwidth anyway .. So , installers have become sloppy in their installations and terminations.. If you crimp it .. It usually works and, for a long while... Until it doesn't work ... by then it could be many years ... as the OP has noted... Patch cables are cheap and easy to find and, the cheap ones work as well as the expensive ones .. for a while anyway. Although my customers regularly complaint about the cost of the pre-made/tested/certified patch cords, we use, we forge on... Our installed networks, some with several hundred, of connections have not experienced one failed connection over that 25 years span... So...
It is likely at the junction ... most (all? ) of those junctions are IDC (Insulation Displacement Contacts) and they have to be performed a certain way but work almost any way you make them ... perhaps one or several contacts points that have been altered (corrosion, likely) enough for that to register.. and it is because you measured it... I doubt it would make one iota of a difference in many applications, even video ...

@MaxwellsEq .. I know what you mean ... One of first job was to replace a coax system complete with "vampire taps" with the "new" RJ-45 hub-based system... The customer was so worried during the installation (not more than we were ) and ,.. Of course it worked better and for so much longer.. All was good , we were heroes...

Peace.

 

[JSmith]

Who tests the cable testers?

... what happens to the breakdown gang when the breakdown gang breaks down?


JSmith

 

[restorer-john]

10BaseT was a joy in comparison.

So old-skool. But I love it.

 

[restorer-john]

Seriously, the cable tester I posted above is pretty much an essential piece of kit. All you ASR f#ckers need to get one and you'll all thank me.

Your DMM can do continuity, but, unless it's a Fluke, it's slow. Slower than you and a probe and a buzzer/LED. Is that cable dead or is that fuse open? Split second test.
Your Fluke DMM can do continuity of course, but try sticking a probe on each and every RJ-45 connection, reliably. At each end. LOL. It just wont happen.
What about an XLR to 1/4"? What is connected and what isn't. Do we have a floating or tied to ground pin?
What cables tie earth and which ones don't?
Is my RCA shorted or just earth compromised?

Some bits of gear are worth their weight in gold. This is one.

Personally recommended...

 

[FrantzM]

Seriously, the cable tester I posted above is pretty much an essential piece of kit. All you ASR f#ckers need to get one and you'll all thank me.

Your DMM can do continuity, but, unless it's a Fluke, it's slow. Slower than you and a probe and a buzzer/LED. Is that cable dead or is that fuse open? Split second test.
Your Fluke DMM can do continuity of course, but try sticking a probe on each and every RJ-45 connection, reliably. At each end. LOL. It just wont happen.
What about an XLR to 1/4"? What is connected and what isn't. Do we have a floating or tied to ground pin?
What cables tie earth and which ones don't?
Is my RCA shorted or just earth compromised?

Some bits of gear are worth their weight in gold. This is one.

Personally recommended...

I have this cable tested and it is a godsent. I second @restorer-john advice: Get one!

peace.