I'm so sorry for the long delay in replying, had to check everything.
What Hardware version is your DCS? Look at the sticker behind or under the camera.
I can't look there, cameras are mounted high up under the ceiling.
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From FW version I presume, HW version is A1.
What Firmware version is currently loaded? Found on the DCSs web page under status.
1.24
What region are you located?
Ukraine
What Mfr and model is the main host router?
Mikrotik RB951G-2HnD
Is the video choppy when locally or streaming from remote?
Live streaming seems to be OK either locally or remotely.
It's Playback System (from D-Link VewCam 4.2.1) that plays choppy video remotely.
How many cameras are connected to the server?
15
what is the server specs? CPU speed and memory?
Intel Core i5 2500K 3.36 GHz
2 x 2 GB DDR3 PC3-10700H RAM (Total 4GB)
What is the local network specs?
1Gb/s link for server and 100Mb/s links for cameras.
Internet spec? Speeds UP and Down?
Tested just now with iperf3, stable 3Mbits/sec between the server and remote notebook with Playback System installed.