Hi form South Africa :)

VectorVESS

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Hey everyone.

Awesome forum here and tons of info! Great resource!

My question :

I'm doing a 32 camera IP install. I want to use 4 x 8port POE switches spread out throughout the buildings and combine them into one switch at the dvr side. Max distance from DVR abou 100m so i can pull say 4 x 60m lines from DVR side and then 8 x 30m lines from POE switch to camears.

The DVR is gigabit able. Can I use 10/100 POE switches and combine them with a gigabit switch at the dvr?

@ 8.2Kbps per camera x 8 = 65Kbps which is well under the 100Mbps rating...... Correct?

So combining 4 x 8 Port POE's into one 4 port Gigabit into the DVR would be OK?

Any input will be greatly appreciated!
 

SouthernYankee

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I do not have that many cameras, and use Blue Iris for recording, but that is exactly how my system is set up. The POE switches are located on different sides of the house to be near the cameras. Then ethernet cables are run from the POE switched to a standard Gigabyte switch, which is also connected to the BlueIris PC.

I am running 2.1MP (1080P) cameras at 15 FPS. The Iframe is 15. Each camera runs at about 310 Kb/s. note small b (bits).

Camera data rate can not really be accurately calculated, it depend on what in in the picture, motion, quality, frame rate, Iframe rate, if using VBR or CBR, type of compression....

It you are using an NVR, the NVR MUST be the correct size for 32 cameras.

Note most DVR are analogue device, NVR are IP network device.
 
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VectorVESS

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Thanks SouthernYankee for the reply.

My bad, yes NVR not DVR :)

The Dahua spec sheet specifies 8192Kbps on H264 (which is the highest rating) and 30fps @ 2Mp (which is also the highest rating). x 8 gives me 65,538Kbps (previous calc was wrong) which equates to 65,5Mbps (if google serves right :), which like I said is well under the 100Mbps rating of the switch, and allows for headroom (ie 2nd channel streaming to mobile device? Or is this done from NVR side?) as there's always real world issues that affect speed.

I just want to confirm that my math is accurate in that 8 cameras won't max out a switch, and the 4 switches won't max out the Gigabit Switch (I'm pretty sure of this part as obviously 10 x 100Mbps switches = 1 x 1Gbps switch). If need be frame rates can be reduce to reduce Kbps, but shouldn't be necessary?

I'm thinking 6/9u case with rack mounted 8 port Gigabit switch and rackmount UPS and the NVR at the bottom.
 
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