Many often ask about running Ethernet beyond its standard distance of 100 meters for UTP, especially when cameras are 400', 500' or more away.
Will it fail?
How We Tested
We tested lengths of Category 6 and 5e cables starting at 1000' (~300m), down to 300' (~90m). Plugs were directly connected to both ends, with three tests performed:
Camera test: We first tested whether cameras would power up and maintain link with a switch, whether pings were received reliably, and whether we could access the web interface/live video. Cameras tested included: 720p, 1080p, 4MP, fixed, PTZ, integrated IR, 802.3af and 802.3at.
Laptop test: Next, we connected two laptops together via the length of cable to see if they maintained link and check connection speed using iPerf.
PoE test: Finally, we measured voltage and wattage using a PoE tester at the far end of the cable to see if power over Ethernet was being properly delivered over the length of cable.
Cat 6 (yellow, below) and 5e (blue) were both used to check for differences in performance due to category rating or simply larger gauge (23 AWG vs. 24 AWG).
The problem is that these things might verry well work and sometimes they won't. There's no guarantee that it will work if you go behind limits.
That's the purpose of the standards: making sure it works reliably if you stick to them.
I have also seen longer than allowed lengths working just fine. I've also seen a lot of them fail, from time to time or all the time. That's the problem, you never know what it will do now and in the future
I've seen things work/not work, as well, and I agree it's incredibly risky to run overlength cables.
This is why we have this note in the report:
Note that we strongly recommend installers follow the TIA/EIA standard and observe the 100m distance limitation. This test was performed to see maximum distance possible, but by violating standards you assume risk of potential future performance issues. Distances over 100m are not tested for longevity, interference issues, etc., which have been properly tested in <100m cables.
Great article! While we've all seen this in the field, it is great to see a reputable source verify some of what is seen in the field. I agree completely that it's generally not worth the risk. That said, there have been a few times where we have a 400' run and have decided to chance it without extenders.
Come to think of it a verifier might not provide much information, as opposed to a qualifier that would actually push packets and see how they do.
The verifier though is going to show FAIL right away on at least the length and probably most other metrics as well. And with these extreme lengths, it is probably legally required to notify the IEEE. ;)
John your tests implies that longer cable lengths work even though you threw in the caveat to follow industry standards. Our field experience says different when it comes to multiple cameras connected to the same POE switch. We had a junior sales engineer do exactly that and almost cost us a customer when cameras started dropping out after several months of working. The more cameras on a switch increases the draw and, in time, will experienced camera failures.
The problem is when an inexperienced installer, after reading a report like yours, ignores the standards and thinks that he can regularly exceed cable length will eventually have failures. The TIA/EIA standard is there for a reason and for you to even suggest that it can be done doesn't mean it should.
Speaking only for myself, Bruce, I'd have to disagree on your general point that IPVM would share responsibility of someone exceeding cable length specs. It is enough to through in there that people should "follow industry standard". Because that is a hard rule that the person doing the job should know. Someone doing a job and not knowing spec's should always be followed despite something being shown to work outside of specs, is poor training, knowledge or discipline on the technician/engineer side, not the fault of a website doing a test. I can show how you can install electrical lines without using safety gear, but it doesn't excuse someone who is supposed to be a properly trained and licensed electrician from not using safety equipment.
It's not IPVM fault if they show equipment can work beyond cable specs and someone uses that as excuse to always do it. They were told to follow specs and as a professional they should know better to do it.
The problem is when an inexperienced installer, after reading a report like yours, ignores the standards and thinks that he can regularly exceed cable length will eventually have failures.
Ok, but the problem is that the information is out there regardless of IPVM, so it becomes more of a question of who responsibly educates them in such matters than if they can be kept in the dark forever.
There's always that tech around with a little more "knowledge" (and a lot more imagination to fill the gaps) eager to "explain" things to the impressionable newbie, that must be considered. Peer-to-peer pressure can be tough to resist.
And inexperienced techs are naturally curious about such things; remember yourself at such a point in your own career... Moreover, some questioning, and even a little experimentation (strictly in-house), is a good sign of an analytical mind and attitude, and something you should nurture.
Setting boundaries is key; And although they may not always agree with you, if they respect you, you can have confidence that you wishes will be heeded, when they're on their own and faced with the inevitable on-site temptation.
Because it's too easy for them if they are not properly schooled in the consequences, to just walk out of there today with everything working fine, but then 9 months down the line you get the shocking news...
So have that "talk" with your techs today, before somebody else does, and by all means support that with factual information from sources like IPVM.
You'll reap the benefits of a more open and productive relationship with your tech.
Lost in all this is that there is at least one company claiming that their gears is (perdon the pun) geared to exceed the 100 meters limitation.
The thing is we should (and likely will ) see this more often. The introduction of extenders to go past the 100 meter limitation is frustrating to say the least: These are not cheap and don't always "play nice" with switches.
We are also of the advice that IPVM in no way encourages >100 meter lengths. The discussion is a good one: some gears do work past the 100 meter limitation. If someone is naive and inexperienced enough to see the article has an endorsement it cannot be attributed to IPVM.
As you rightly point out following the standards is the only way to go, by way of an example I recently discovered at a coal processing plant located in Australia, 4 IP PTZ cameras with CAT5e cable runs at 150m+ that were not working at all. These cameras had initially been working for a number of months then 1 by one they stopped.
I've seen this as well where a temp installation that marginally exceeded 100m (10m+) worked fine for a couple of months and then stopped completely. I'd be interested to figure out what process caused the failure by aging as the physical installation appeared fine. The cam/nvr combo worked fine with a short test jumper and identical new devices refused to work in the field. Had to install a field switch to shorten distance.
Judging from my personal experience and what some other members have been mentioning, I would like to request an update to this test with actual wattage draw numbers for the distances and grades of cable used.
Same as other people here who did not run into an immediate problem going past the max distance, but problems developed later. We've had a couple cases of cameras just occasionally dropping off for no good reason and they'd come up after a switch reboot done remotely in the office. We even replaced a switch and a camera in one instance.
We finally got a tech out who knew what they were doing and in one case the cable was around 360ft and the other around 400ft.
If you violate the cable length spec you're in trouble. Doesn't matter how many magic tools you use to test it. One screw-up and you'll get to explain it to the customer. Get your cables "certified" (means you burned a grand on a second vendor with actual testing gear who came in, did a test, and delivered an actual report.)