tool
ONVIF Device Test Tool (if restrictions router forwards multicast packets to other network segment, only search to hosts on the same network segment) search tool
ONVIF Device Manager management tools
Details: https: //www.cnblogs.com/lsdb/p/9157302.html
Onvif principle found
udp multicast transmission based on ONVIF protocol to 239.255.255.250:37020, the device listens 239.255.255.250:37020, receive instruction, will send multicast machinery, returns the device information, the device will also be sent to 239.255.255.250:37020 multicast information.