Recording and playback are core functions within our systems. We recognise the need to retain data for a long time but without the worry of having to manage it.  The recorder from Ledwood Technology is configured to work on a fixed file size, automatically overwriting the oldest data when the limit is reached. The limit however, can be up to the file system limit; a typical system of two CCTV cameras, radar, AIS and two VHF channels will store about 4-5 weeks worth in a 1.5Tb file. For longer recording times, more off the shelf IT data storage can be used. 

The recording file is typically stored on a RAID array attached directly to the computer that is providing the recording functionality. In larger systems it is possible to have a dedicated recorder using standard, off the shelf, high availability storage NASs and SANs.

All of the sensor data is stored in the recording file (i.e. Radar, CCTV, AIS, VHF and so on) this enables synchronous playback; an operator can connect to the recording and play back the data as if it were happening live, without having to manually synchronise video, audio and radar. 

When playing back radar, operators can acquire tracks, play back tracks that were recorded, as well as adjusting the radar processing controls to perhaps obtain a better picture that was available at the time. 

Recordings can be extracted from the system for permanent archive, for example, to accompany incident reports.