Getting good results tests a cheap PoE to extend cable run

105437

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As a test, I purchased this cheap PoE switch to see how the "extend" function worked. Anyone else try this function on a cheap PoE switch before? How'd it work for you?

First test
Main PoE switch -> 80' -> DMARC side of house (keystone) -> 170' -> IP Camera = Persistent ping shows packet drops every 20 - 30 seconds.

Second test
Main PoE switch -> 80' -> DMARC side of house (keystone) -> Input to cheap switch in "extend" mode -> 170' -> IP Camera = Persistent ping shows no packet drops.
 
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What's the purpose of this 'extend' function? Longer POE distance?

I do not get the first test. Switch to DMARC and then 170' to camera. Why does switch cable goto DMARC?
 

105437

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What's the purpose of this 'extend' function? Longer POE distance?

I do not get the first test. Switch to DMARC and then 170' to camera. Why does switch cable goto DMARC?
The DMARC is at the side of my house. I have two Cat 6 cables that run from there to my IT closet. I have keystones at the DMARC for these Cat 6 cables. When I did all of the low voltage wiring in our new build, I didn't home run a cable to the location I'm testing from the IT closet. Instead, I used one of the DMARC Cat 6 cables, which are not in use for anything as my best way to do this test.

The extend function of this switch is explained below.
1659317803039.png
 

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Considering 170' is a little over half the spec distance I think the cheap switch isn't actually meeting spec in the first place.
The first test doesn't use the switch and there's packet loss, the second test uses the switch and there's no packet loss.
 

Teken

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This was created as a novel band aid idea vs using the correct hardware to repeat the signal. Doing so would assure a 1GB connection, throughput, and data integrity.

There are going to be people who chime in about A camera doesn't use this - this speed is fine - etc. This only shows the lack of understanding its not simply about a ping / latency. :facepalm:
 

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This was created as a novel band aid idea vs using the correct hardware to repeat the signal. Doing so would assure a 1GB connection, throughput, and data integrity.

There are going to be people who chime in about A camera doesn't use this - this speed is fine - etc. This only shows the lack of understanding its not simply about a ping / latency. :facepalm:
It's definitely some sort of hack. There are several cheap switches out there that have this extend "feature". I like to test things and this is interesting to me. I'm in no way saying it's a substitute for a 1GB connection. The camera I'm testing this switch with is pulling a steady 1.2 Mbps, well under the link speed.
 
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Teken

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It's definitely some sort of hack. There are several cheap switches out there that have this extend "feature". I like to test things and this to be interesting. I'm in no way saying it's a substitute for a 1GB connection. The camera I'm testing this switch with is pulling a steady 1.2 Mbps, well under the link speed.
For the benefit of others let me try to explain my views and whether or not you agree / disagree. You and others can see why I hold these view(s) as it relates to POE / Video. Back in the day a whole bunch of smart people came together to define, design and release a Standard.

This was followed with certification to insure a predictable outcome.

All of this hinges upon everything in the various links to meet those Standards. When just one thing doesn't meet that standard it introduces unexpected results, performance, and outcomes. Just think about something as simple as maximum distance of POE (100 meters / 328 feet).

Something that is well known and well defined is exceeded.

On the other extreme you have millions of people and companies using CCA cable. Worse they are using patch cable in the wall for home runs to connect to their various POE Devices.

Not only is that illegal its dangerous . . .
 
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