Security system compatibility is the degree to which devices from different manufacturers work together. It depends on open protocols such as ONVIF for video and OSDP for card readers, and on whether the management platform supports third-party hardware without dropping features.
Compatibility is usually discovered during an upgrade, when a new camera arrives and the existing recorder will not accept it. Checking before a purchase costs far less than replacing working equipment.
Standards that actually help
ONVIF profiles define how video is streamed and discovered, while OSDP covers reader-to-controller communication. Profile support covers the basics; analytics, firmware updates and warranty service may still require the original vendor.
Where lock-in hides
Licensing, proprietary cabling, cloud-only configuration and firmware update policies can tie a site to one supplier even when the protocols are open. Read those terms before standardizing on a platform.