Storage Interfaces in Video Surveillance

Storage units are essential parts and/or a peripheral component of each video surveillance recording solution and are divided into two main categories: external and internal. Internal storage is usually a set of hard disks which are available in different capacities and technical specifications. Examples of external storages are removable flash disks, portable HDDs, etc. In all of the storage units the interface plays an essential role due to its functionality as the gateway of all of the data transferred between the storage unit and the recorder. The speed and performance of the data interface can be the performance bottleneck of the recording solution and may determine the maximum devices that the recorder can optimally support. The ATA interface has been originally developed for the internal HDDs of desktop PCs, while Small Computer System Interface (SCSI) has been developed for servers and large scale storage systems. Due to demand for high speed data transfer, hard disk interfaces are moving from parallel to serial transmission. For instance, Serial Attached SCSI (SAS) will replace Parallel SCSI and Fiber Channel (FC), Serial ATA (SATA) will replace Parallel ATA. This report describes the features of the main interfaces involved in storage systems. Also, the application of several interfaces in video surveillance is studied and the best choice for video recorders is discussed. At the end of the report, a comparative study is presented.