Advice on iperf3 test results

[freddyq]

What length is that cable?
Quite a difference in the results.

With apologies for the dumb question - just trying to guess what might be the problem here -
You've confirmed that the wire colour sequence for your crimping is correct, and is T568B.
Can you confirm, maybe by comparison with the pre-made cable, that the wires are set in the correct direction? ie Pin 1 isn't actually Pin 8.

The self-crimped cable I used is very short in length, maybe 30 inches or so.

And yes, I've just checked the wire sequence of the pre-made cable and if I turn the connector so that I'm looking at the underside of it, I see the colour sequence as I described it. The same is true for my self-crimped cable so the sequences do match up...

 

[DavidR1]

A few more questions:

When crimping your own connectors, are you keeping the twist in the individual pairs for as long as possible before they must separate to be inserted into the connector?

The cabling you have is solid as opposed to stranded I presume? And while I'm asking, I'll also ask if it's CCA or pure copper - something I should have asked earlier since you intend to use PoE.

Patch panel to wall jack runs are typically done with solid wire, while patch cords are usually made from stranded; not all RJ45 connectors work well on solid wire. Do you have access to any other RJ45 connectors that aren't from the batch you've been using thus far?

Do you have access to a punch down tool? Or were you going to skip pulling the runs to a patch panel and just plug them directly into your switch/NVR? I ask because we could test the runs your contractor installed without the RJ45's crimped on using keystone jacks (available all over for just a few bucks) and your "known good" machine terminated patch cords.

 

[freddyq]

A few more questions:

When crimping your own connectors, are you keeping the twist in the individual pairs for as long as possible before they must separate to be inserted into the connector?

The cabling you have is solid as opposed to stranded I presume? And while I'm asking, I'll also ask if it's CCA or pure copper - something I should have asked earlier since you intend to use PoE.

Patch panel to wall jack runs are typically done with solid wire, while patch cords are usually made from stranded; not all RJ45 connectors work well on solid wire. Do you have access to any other RJ45 connectors that aren't from the batch you've been using thus far?

Do you have access to a punch down tool? Or were you going to skip pulling the runs to a patch panel and just plug them directly into your switch/NVR? I ask because we could test the runs your contractor installed without the RJ45's crimped on using keystone jacks (available all over for just a few bucks) and your "known good" machine terminated patch cords.

So yes I tried to keep the twist for as long as practically possible but it's quite a fiddly job as you know, especially for someone who doesn't do it all the time so I did my best

The cabling is UTP Solid Core, I actually sought advice before buying the cable and pointed out I was going to be using it for PoE cameras and was advised to get this type. I have a big reel of it.

Re the RJ45 connectors, I don't have access to any other connectors other than those I ordered to crimp these cables but I guess I could buy some. Looking back at my correspondence from that time, I was also pointed in the direction of this crimping system although I think I just ended up buying a crimping tool and a bunch of CAT6 connectors. I don't have a punch down tool, as you say I was just intending to plug the switch end straight into the switch and the other end straight into the camera. Now that you're asking this I'm wondering whether because this is CAT6 UTP solid core, and trickier to crimp maybe I didn't do a 100% job on the crimping which is causing these results. Maybe I should buy the crimping system I've linked above...? Although I'd hate to buy that only to find that wasn't the cause of the problem!

 

[DavidR1]

I figured you kept the twist but had to ask.

As mentioned previously, there are different types of RJ45 connectors - not all of which were intended to work with solid wire. Some pictures showing the difference here: The Differences between Solid and Stranded Cable. The ones you currently have may also be for both types of cabling, though it might take some squinting to determine if it’s not clearly marked on the package. The feed-through style connectors from the place you linked specifically state being suitable for both solid or stranded, but I’d see if anyone offers further suggestions here before spending money on a new crimper and ends.

Unrelated to the connectors, I would be also sure to double check that the wire you have is “pure copper” and not ”copper clad aluminum” or ”CCA”. See the thread here on it. Presumably people here steered you in the right direction (I didn’t find any links to specific brand of cable you purchased in a quick search of past posts), but there’s a lot of shady junk out there, and the people marketing and selling it go out of their way to make it hard to tell the difference.

Normally, I’d just say install your cameras and see where you wind up; I’d imagine few DIY, homeowner types are actually testing their cable before hooking stuff up. In your case though, you’ve already done some testing and it seems that perhaps something is actually wrong.

Maybe someone here lives near you and could spare a few connectors or loan you a different crimper to try? Or could loan you a punch down tool and a couple of spare keystone jacks just for testing? Ideally, you’d just know a cable installer with a qualification/certification tester that could pinpoint the problem in seconds...but I assume you’d have mentioned it if that were the case.

Unfortunately, I’m out of ideas that won’t cost anything at the moment. Hopefully someone else here can think of something and make a suggestion.

 

[freddyq]

I figured you kept the twist but had to ask.

As mentioned previously, there are different types of RJ45 connectors - not all of which were intended to work with solid wire. Some pictures showing the difference here: The Differences between Solid and Stranded Cable. The ones you currently have may also be for both types of cabling, though it might take some squinting to determine if it’s not clearly marked on the package. The feed-through style connectors from the place you linked specifically state being suitable for both solid or stranded, but I’d see if anyone offers further suggestions here before spending money on a new crimper and ends.

Unrelated to the connectors, I would be also sure to double check that the wire you have is “pure copper” and not ”copper clad aluminum” or ”CCA”. See the thread here on it. Presumably people here steered you in the right direction (I didn’t find any links to specific brand of cable you purchased in a quick search of past posts), but there’s a lot of shady junk out there, and the people marketing and selling it go out of their way to make it hard to tell the difference.

Normally, I’d just say install your cameras and see where you wind up; I’d imagine few DIY, homeowner types are actually testing their cable before hooking stuff up. In your case though, you’ve already done some testing and it seems that perhaps something is actually wrong.

Maybe someone here lives near you and could spare a few connectors or loan you a different crimper to try? Or could loan you a punch down tool and a couple of spare keystone jacks just for testing? Ideally, you’d just know a cable installer with a qualification/certification tester that could pinpoint the problem in seconds...but I assume you’d have mentioned it if that were the case.

Unfortunately, I’m out of ideas that won’t cost anything at the moment. Hopefully someone else here can think of something and make a suggestion.

So these are the connectors I've used. Having a look through the Amazon product description doesn't mention whether these can be used with solid core cable, some people have asked questions on this topic with some saying they work, some saying they don't.

The cable is definitely not CCA because I've found the emails I exchanged with the support person online from the place I bought it and he specifically mentioned I should avoid CCA cable and ensure it UTP Solid Core. He gave me a link to the cable I need and that's the one I ordered. So that can definitely be ruled out.

I have thought of a potential solution in case of worst case scenario that the cables have somehow become dud over time and even re-crimping doesn't improve test results. It involves running new cable but I don't think I'll need to run it all to the same single location the current cables are running to, which avoids doing ugly cable runs inside or outside. But I'll post my plan for validation in a separate post here...

Re professional cable installer, I don't know one unfortunately but I might ask some friends...

Thanks for your help - still very much appreciated.

 

[freddyq]

So I posted this as part of another thread about camera choice but more pertinent here..

My current CAT6 cables are all running to a small storage area in the house where I also have my router and a PoE switch so I planned to plug the cables coming from the camera locations into the switch and then also have an NVR or PC connected to this switch in the same location.

Now if the camera cables are dud, I might be able to run new cables as part of some building work about to be done to the front and side/rear of my house. Only snag is that if I have to run the new cables back to the same storage area then that will require running the cables along internal/external walls which I don't want to do (the dud cables are running under floors and ceilings because they were laid when the house was renovated).

So my idea is that for the camera at the front of the house I run a new cable as part of the building work which will happen at the front of the house and take it to the storage area which is also at the front of the house - this cable can be hidden behind walls and ceilings to get to the storage area if done with the building work. For the cables to the side and rear cameras, I can again run new cables as part of building work but these would run to an office room which is being built. Now cable 3 in my originally posted test results is already running from the current storage area to this new office room location so if I plug cable 3 into another PoE switch which would be in the office room, I could then plug the two new cables for the side and rear cameras into this second PoE switch. I could also plug a BlueIris PC into this second PoE switch in the office room.

So will this work even though one of my cameras is connected to switch 1 and the other two cameras and the BI PC are connected to switch 2? Also, the main dependency in this solution is cable 3 because that is the one creating the link between the current and new locations and is the only 'old' cable in this setup. That cable has the best results of all 4 cables I tested in terms of packet loss but I'll defer to those with more knowledge in terms of whether the results of that cable are good enough to use for this solution or not...

 

[alastairstevenson]

I can't think but that we're missing something here.
Whilst recognising that cable ends need to ideally be matched against the type of cable, a bad crimp would give a broken connection as opposed to a degraded connection.
You've confirmed the wiring scheme that you've applied, and the correct order of the colours. And even confirmed you've maintained the twists as best you can
And your tests have demonstrated a big difference in results between even your 30cm cable and a pre-built one.

What length is still on the unused drum?
If it's under 100m you could (if you feel further inclined to experiment) attach a connector to each end and run tests.
Can you attach a picture of one of the crimped ends?

 

[freddyq]

I can't think but that we're missing something here.
Whilst recognising that cable ends need to ideally be matched against the type of cable, a bad crimp would give a broken connection as opposed to a degraded connection.
You've confirmed the wiring scheme that you've applied, and the correct order of the colours. And even confirmed you've maintained the twists as best you can
And your tests have demonstrated a big difference in results between even your 30cm cable and a pre-built one.

What length is still on the unused drum?
If it's under 100m you could (if you feel further inclined to experiment) attach a connector to each send and run tests.
Can you attach s picture of one of the crimped ends?

I'm not sure how much is still unused on the drum to be honest but fairly sure it'll be less than 100m. I think what you're getting at is that the whole drum might be faulty?

And yes, I will attach a pic of one of the crimped ends later today...

I've also got a cable tester but I believe those only really check sequencing of wiring, not bandwidth.

 

[freddyq]

As mentioned previously, there are different types of RJ45 connectors - not all of which were intended to work with solid wire. Some pictures showing the difference here: The Differences between Solid and Stranded Cable.

Just been reading the post you linked to and I am fairly sure (although I'll check tonight) that the RJ45 contact design on the connectors I've used is the third type in that post, i.e. where it pierces and embeds into the strands of the conductor. Interestingly, the post says those types are for stranded cable only. I wonder if that's the issue...

 

[alastairstevenson]

No, I'm not suggesting the cable on the drum is faulty, that's not likely, although physical defects can happen.
I thought it might be a way to empirically experiment.
Eg Run tests, confirm they give consistent results.
Re-do an end and see if anything changes. Easier than running new cables.

 

[freddyq]

No, I'm not suggesting the cable on the drum is faulty, that's not likely, although physical defects can happen.
I thought it might be a way to empirically experiment.
Eg Run tests, confirm they give consistent results.
Re-do an end and see if anything changes. Easier than running new cables.

Ah right - I think I am leaning towards re-crimping the cables anyway because I'm not 100% convinced the connectors I've used are best for the solid core cable I've crimped them onto. I will find a small pack of connectors specifically for solid core cable, crimp those on and then re-test. Re-crimping is still a relatively small job and worth doing compared to re-running new cables...

 

[DavidR1]

I feel @alastairstevenson has to be right and we're just missing something. Close-up pictures of both ends of your short cable might help someone spot an issue. Please share the markings on the cabling too if you don't mind.

The solid vs stranded connector concern is probably a red herring; my apologies for that. The fact that you have similar issues with your short, 3' homemade cable rules out so many other variables it was hard for me not to keep coming back to something about the connectors being to blame. As has been pointed out, it's much more likely that an issue there would result in a non-functioning cable rather than a poor-performing one.

 

[freddyq]

I feel @alastairstevenson has to be right and we're just missing something. Close-up pictures of both ends of your short cable might help someone spot an issue. Please share the markings on the cabling too if you don't mind.

The solid vs stranded connector concern is probably a red herring; my apologies for that. The fact that you have similar issues with your short, 3' homemade cable rules out so many other variables it was hard for me not to keep coming back to something about the connectors being to blame. As has been pointed out, it's much more likely that an issue there would result in a non-functioning cable rather than a poor-performing one.

Fair enough - I'll post some close up pics tonight in the hope they might give some clues...

 

[freddyq]

OK so here are close up pics of the underside of both ends:






Pics of marking on the cable:





Side view of one of the ends:



Top view of one of the ends:

 

[DavidR1]

For future plugs you crimp, you should trim the wire pairs such that when they are all fully seated, you get the cable's outer jacket under the triangle-shaped portion at the back of the plug. When you crimp the connector, that part of the plug gets pushed in and holds onto the jacket.

Would you please take and share one more set of pics from the end of the connector, such that you can see each individual wire is fully seated?

 

[freddyq]

Yea I've always tried to get the outer jacket to end up under that gripper but I've only managed it on a few occasions. I've seen some connectors which allow the wire pairs to pass straight through the other end - I think I'll get those next time as I think they will make it much easier to achieve that.

Anyway, pics from the end of each connector:

 

[DavidR1]

Nice bokeh! Well, they at least look like you'd expect them to look.

You can try some additional crimps on the remaining spool of cable as @alastairstevenson suggests for testing purposes. And/or try another batch of connectors. I'll have another look at the pics when I get home this evening and see if there's anything else I can think of. Hopefully in the mean time, more eyes and minds will see something I've missed.

 

[freddyq]

Nice bokeh! Well, they at least look like you'd expect them to look.

You can try some additional crimps on the remaining spool of cable as @alastairstevenson suggests for testing purposes. And/or try another batch of connectors. I'll have another look at the pics when I get home this evening and see if there's anything else I can think of. Hopefully in the mean time, more eyes and minds will see something I've missed.

Thanks - those are actually from my phone!

Yes I think I will crimp another new cable from the spool and test that - would be interesting to see if I get the same results or not..

 

[freddyq]

So I posted this as part of another thread about camera choice but more pertinent here..

My current CAT6 cables are all running to a small storage area in the house where I also have my router and a PoE switch so I planned to plug the cables coming from the camera locations into the switch and then also have an NVR or PC connected to this switch in the same location.

Now if the camera cables are dud, I might be able to run new cables as part of some building work about to be done to the front and side/rear of my house. Only snag is that if I have to run the new cables back to the same storage area then that will require running the cables along internal/external walls which I don't want to do (the dud cables are running under floors and ceilings because they were laid when the house was renovated).

So my idea is that for the camera at the front of the house I run a new cable as part of the building work which will happen at the front of the house and take it to the storage area which is also at the front of the house - this cable can be hidden behind walls and ceilings to get to the storage area if done with the building work. For the cables to the side and rear cameras, I can again run new cables as part of building work but these would run to an office room which is being built. Now cable 3 in my originally posted test results is already running from the current storage area to this new office room location so if I plug cable 3 into another PoE switch which would be in the office room, I could then plug the two new cables for the side and rear cameras into this second PoE switch. I could also plug a BlueIris PC into this second PoE switch in the office room.

So will this work even though one of my cameras is connected to switch 1 and the other two cameras and the BI PC are connected to switch 2? Also, the main dependency in this solution is cable 3 because that is the one creating the link between the current and new locations and is the only 'old' cable in this setup. That cable has the best results of all 4 cables I tested in terms of packet loss but I'll defer to those with more knowledge in terms of whether the results of that cable are good enough to use for this solution or not...

Just on this - I know we're still hoping to resolve the issue with my existing cables but could someone confirm if the above network setup would work?

 

[DavidR1]

Just on this - I know we're still hoping to resolve the issue with my existing cables but could someone confirm if the above network setup would work?

Cable 3
[ ID] Interval Transfer Bandwidth Total Datagrams
[ 5] 0.00-1.01 sec 3.98 MBytes 33.2 Mbits/sec 510
[ 5] 1.01-2.02 sec 4.30 MBytes 35.7 Mbits/sec 550
[ 5] 2.02-3.02 sec 3.67 MBytes 30.6 Mbits/sec 470
[ 5] 3.02-4.01 sec 3.36 MBytes 28.4 Mbits/sec 430
[ 5] 4.01-5.01 sec 3.59 MBytes 30.4 Mbits/sec 460
[ 5] 5.01-6.02 sec 3.75 MBytes 30.9 Mbits/sec 480
[ 5] 6.02-7.01 sec 3.67 MBytes 31.2 Mbits/sec 470
[ 5] 7.01-8.00 sec 3.67 MBytes 31.0 Mbits/sec 470
[ 5] 8.00-9.02 sec 3.75 MBytes 30.9 Mbits/sec 480
[ 5] 9.02-10.02 sec 3.67 MBytes 30.8 Mbits/sec 470
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bandwidth Jitter Lost/Total Datagrams
[ 5] 0.00-10.02 sec 37.4 MBytes 31.3 Mbits/sec 1.831 ms 166/4790 (3.5%)
[ 5] Sent 4790 datagrams

There's nothing wrong at all with having multiple switches (PoE or otherwise) in your network topology. It's the norm in offices and datacenters and there's many people here doing something similar (myself included).

Cable 3 has really lousy throughput though unfortunately, even if it's showing better loss numbers compared to the other runs. Even if "it works", that's going to limit traffic over that link between the office and your router - Blue Iris, some cameras, and possibly a wired office computer, etc. Frankly, a powerline adapter or even wireless link offers better connectivity. And without knowing what the problem is, who's to say it won't get worse or stop working altogether after you've decided to make it a key part of your infrastructure?

Since there's already construction happening, it makes sense (to me at least - it's not my money or mess in my living space) to do things right rather than complicating an already problematic install. Based on how you had your current cabling installed, I assume you don't have accessible attic/basement space to run wires? A cable installer can run things through finished spaces with minimal repairs needed, if it came to that, and you'll already have someone doing drywall and paint so they should be able to do the touch-up at minimal added expense. A qualified cable installer will also punch down a patch panel and wall jacks where needed, and you'll be guaranteed properly working runs when they're finished.

Sorry this has turned a basic installation plan into such a nightmare project for you. If you were local, I'd happily volunteer to stop by with everything needed to figure it out and complete the installation, but solving it over the internet is a challenge. It's honestly never this complicated; there's clearly something we're missing....