PoE cameras using PoE switch
- Thread starter bigone5500
- Start date
RandyDSok
Well-Known Member
Ok... since this is a technical subject... we need to be a bit more picky about the details that are being discussed... You have to consider ALL of the components to determine what speed limitations may or may not exist.
bigone started by asking if Cat6 would handle the required data... The problem with the question was it was only about the potential speed of just the cable and didn't take into account the port limitations that Tony brought up... and what was not mentioned, the total speed the switch is capable of handling, which myself I can only mention it since I don't know it's full specs because that is outside the scope of my knowledge as well.
So to address cabling specs first.... see the chart I've attached that lists the specs for Cat3 up to Cat7 cabling. It shows for Cat6 as mentioned, 10Gbps @ 250Mhz frequency and I believe this is for a 100 meter run of cable. Longer runs will degrade that performance but probably not enough to worry about here even if it is worth knowing about it.
Next you need to know the speeds the ports on the switch are capable of handling. 1 Gbps is pretty good for most needs as Tony mentioned.
What wasn't mentioned is the total processing the switch can handle. Most switches, except the most expensive ones, can't handle all of their ports operating at their rated speed. They can only process up to a certain percentage of that total. Now Tony did mention that the NVR was only connected to a single 1 Gbps port so that is where it will be "bottlenecked" at. But we still need to know there is also a processing limit among all of the ports. In this case the limit will be the port the NVR is capable of handling... but if traffic wasn't limited to just that direction ( to/from the NVR ) then you would need to consider all of the traffic and their routes in the rest of the network.
As I type this... I don't know we established what speed port the NVR actually has on it. That also needs to be considered as another possible bottleneck if it were to say have just a 10/100 Mbps port on it.
To sum it up... it isn't just about the pipe being used but the complete network of them and the limits that each bring.
bigone started by asking if Cat6 would handle the required data... The problem with the question was it was only about the potential speed of just the cable and didn't take into account the port limitations that Tony brought up... and what was not mentioned, the total speed the switch is capable of handling, which myself I can only mention it since I don't know it's full specs because that is outside the scope of my knowledge as well.
So to address cabling specs first.... see the chart I've attached that lists the specs for Cat3 up to Cat7 cabling. It shows for Cat6 as mentioned, 10Gbps @ 250Mhz frequency and I believe this is for a 100 meter run of cable. Longer runs will degrade that performance but probably not enough to worry about here even if it is worth knowing about it.
Next you need to know the speeds the ports on the switch are capable of handling. 1 Gbps is pretty good for most needs as Tony mentioned.
What wasn't mentioned is the total processing the switch can handle. Most switches, except the most expensive ones, can't handle all of their ports operating at their rated speed. They can only process up to a certain percentage of that total. Now Tony did mention that the NVR was only connected to a single 1 Gbps port so that is where it will be "bottlenecked" at. But we still need to know there is also a processing limit among all of the ports. In this case the limit will be the port the NVR is capable of handling... but if traffic wasn't limited to just that direction ( to/from the NVR ) then you would need to consider all of the traffic and their routes in the rest of the network.
As I type this... I don't know we established what speed port the NVR actually has on it. That also needs to be considered as another possible bottleneck if it were to say have just a 10/100 Mbps port on it.
To sum it up... it isn't just about the pipe being used but the complete network of them and the limits that each bring.
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bigone5500
Well-Known Member
So my switch doesn't have this uplink port. It has the 9T and 10T ports on the front. I don't think they will work but have read that I can use a regular PoE port to connect to the NVR. Wouldn't this damage the NVR?
Tony
Staff member
You can use a standard RJ45 port on the switch, and the switch should sense if there is a request for PoE power (unless it is old) and even then, it shouldn't damage the NVR even if there is power on the line. You can manually go into the switch and turn it off though for the port you are wanting to use.
bigone5500
Well-Known Member
bigone5500
Well-Known Member
So I got another switch. It has some Connectors on back. Is the eps connector required for PoE use?
RandyDSok
Well-Known Member
You can not ask a technically based question generically... Look for the manual for that specific make/model... read the manual.
EPS stands for Electrical Power Supply.... currently it is most commonly used on PC computer systems to supply power to other devices. I did find a reference to a power cable used in some car... and nothing like what you pictured on a page of Google results.
bigone5500
Well-Known Member
I'll get a manual later. I was just wondering if it is required for poe use. The manual will uncover the truth!
bigone5500
Well-Known Member
OK. The eps connector is for an external power supply. It is used to give the switch more power per port. It is hot pluggable. I do not need it to use the switch. The switch provides up to 30w per port.
bigone5500
Well-Known Member
After reading a bit more in the manual...
