First, you need to change the format of the secondary stream to MJPG.
Leave the default http port at 80
The only condition is that only one connection is allowed at a time, this can be useful for home automation applications, but for web it can be inconvenient.
Also, remember that it does not work in Internet Explorer:
http://<user>:<password>@<camera_ip_address>:http_port>/ISAPI/Streaming/streaming/channels/102/httpPreview
http://admin:password@174.28.223.64/Streaming/channels/102/httpPreview
All the cameras that appear in the following search have this system with the limitation that we have commented
https://www.visiotechsecurity.com/es/search?keyword=DS-2CD2
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