Edge storage is recording video on or right beside the camera — most often a microSD card in the camera, sometimes a small local recorder — instead of (or in addition to) sending every stream to a central server. The camera writes its own footage locally, and the VMS retrieves it on demand, commonly over ONVIF Profile G. It turns each camera into a small, self-sufficient recorder.
Its defining value is resilience. If the network link or the central recording server fails, a camera with edge storage keeps recording to its own card, and the VMS backfills the missing footage once the connection returns — so a network outage becomes a gap to fill rather than footage lost forever. This "record at the edge, sync later" pattern underpins reliable VSaaS and hybrid designs, and it cuts continuous upload because full video need only move when something is actually requested.
The pitfalls are capacity and durability. An SD card holds far less than a server array, so edge storage is a buffer and a safety net measured in days, not a long-term archive; retention beyond the card's size still needs central or cloud storage. Cards also wear out under constant writing, so surveillance-rated, high-endurance cards are essential and card health should be monitored, or a silently failed card leaves a camera with no local recording exactly when it is needed. Use edge storage to survive outages and reduce bandwidth, backed by central storage for long retention.
