Adding Switch in Network Wreaks Havoc!!!

[James Wilson]

I have an Amcrest 16 channel network video recorder (NVR). Model number NV2116. I have connected it to 16 cameras. The recorder is in an office that has only one network cable running back to the main network switch. I need to add a switch in the office where the NVR resides in order to connect a PC to the network.

Everything works fine when connected directly to the main switch.

See links:

Network schematic with no switch

Network graph with no switch

The issue is that when I add a switch between the NVR and the main switch I get erratic network reception by the NVR.

See links:

Network Schematic With Switch

Network graph with switch in place


This causes stuttering and dropped frames in the recordings. When I connect the NVR directly to the main switch, everything runs smoothly.

I have tried three different network switches, all with the same result of erratic network reception by the NVR. I have no clue why adding the switch would make any difference.

Network switches I have tried are all 10/100. I have not tried a GB switch yet but I am thinking this will not matter.

Can anyone offer a solution short of running a dedicated network cable back to the main switch? Also, I am very interested to know WHY adding a switch in this way would make any difference. Something to do with spanning tree protocol? I am clueless!

Thanks for reading!

 

[Genx87]

Switch models involved? Video is pretty bandwidth intensive. Maybe the 4 port switch is not upto the task?

 

[Kartajan]

1) Are you certain that you were inserting a switch and not a hub? Your throughput graph looks like a hub setup that is being throttled by other signals...

2) I would get a gigabit switch, if for no other reason than the likelihood of having the most current hardware and warranty support.
<I take it that you do not have an onsite network/ IT person>

 

[Kartajan]

https://www.newegg.com/Product/Prod...38&IsNodeId=1&bop=And&Order=PRICE&PageSize=36

some highly "reviewed" netgear and tplink Gigabit switches are under $20...

 

[PliotronX]

Are the switches you have tried PoE? What is their rated voltage and wattage? Are they unmanaged?

 

[Gryz]

When I just read the subject, my first thought was: "LOOP!!!".

The diagrams look nice and loop-free. But in the real world, the cabling is never as it is in the diagrams. A user can have connected his own device somewhere. A cheap switch maybe. And you're not aware. Or he might have put a cable into another outlet, connecting 2 LANs where they are not supposed to connect.

If I were you, I'd look at the network traffic when the network is having troubles. Do you see the number of packets going up ? Causing some links to be congested ? Can you look at the packet with a sniffer/tcpdump/wireshark ? Do the TTLs of some packets go down to 0 ? Lots of ways to detect whether you have a loop.