This article will explain the feature in Nebula where we can provide a centralized platform to monitor and maintain any surveillance equipment deployed in the site with WS-Discovery protocol. This is because LLDP is not a commonly used protocol for device discovery.
Background
ONVIF is an organization whose mission is primarily focused on promoting effective interoperability between IP-based physical security products (IP cameras, NVR). At the same time, one of the core specifications listed by ONVIF is the support of a protocol called “WS-Discovery” for device discovery.
What is WS-Discovery?
Web Service Dynamic (WS) Discovery uses multicast delivery to search for IP-based security products within the network. It uses the destination address 239.255.255.250 and the UDP port 3702.
How does WS-Discovery work?
Switch with ONVIF enabled listens for WS-Discovery messages every 30 seconds by sending out probe messages to the ports with ONVIF enabled. If the device doesn't respond in 120 seconds and see no activity, if the port is disconnected, or the link is down, the switch unlearns the device.
ONVIF Discovery – Device Type
IP Camera
- Port that receives a Probe-Match message identifies IP cameras
Network Video Recorder (NVR)
- Port that receives a Probe message identifies NVR
Others
- A port that learns a neighbor device through LLDP only
- A port that has more than one online (responsive) device
ONVIF Handshake process
How to Configure ONVIF
Go to:
Site-wide > Configure > Switch > ONVIF configuration
1) Set up the VLAN ID (up to 2 VLANS)
2) Select the switch you want to listen to ONVIF messages and which ports (divided by "," for multiple ports or "-" for a range of ports)
Surveillance - Gaining ONVIF Information
Go to:
Site-wide > Monitor > Switch > Surveillance
You can see what type of devices are connected and the number of units connected on the right top.
You can also see the Neighbour Information:
1) information learned from BOTH WS-Discovery and LLDP
2) information learned from WS-Discovery is prioritized
3) information as greyed out if the device is disconnected or stops sending LLDP/ONVIF
Also, you can view more information by clicking on the "Discovered devices":