Frame drop is one of the key problems in IP surveillance systems. The consequence of dropped frames are recording gaps which translate into lost images that could cost a company unmeasurable financial damages.
Rasilient sought to design a recording server combined with a storage system that could support up to 1,000 cameras and over one petabyte of storage. “We wanted the NFD Systems to be the basic building block of large projects, for example we recently had a project in Qatar with over 2,600 cameras and eight petabytes of storage which used several of these systems,” explained Wan, Director of Middle East Operations at Rasilient Systems.
Rasilient’s solution was designed with video surveillance in mind. “Other storage companies are IT-based, and the storage technology employed by other vendors caters to random access, i.e., including read and write. Whereas our system is built for over 95 percent write and minimum read access,” remarked Wan.
Rasilient chose the Seagate Technology's SkyHawk drive to be implemented in their systems. “The biggest reason we chose Seagate was the reliability and support we were getting during the qualification process,” explained Wan. “It allowed us to lower the total cost of ownership and achieve great performance in large scale deployments. After switching to Seagate we have lower disk failure rates and we also achieved a remarkable NFD (no frame drop) during our solution partner certification with Milestone System’s XProtect VMS,” Wan added.
Under the Milestone certification criteria, a frame drop rate of under 0.1 percent is acceptable. Rasilient’s achievement was even more remarkable: “We had 1,000 2-MP simulated cameras streaming for 72 hours at 25 FPS at HD quality,” said Wan. “To make the test even harder and stress test the system even more, we increased the recording bandwidth to 2.1 GB/s. In the meantime, we simulated a disk failure by pulling out a drive out of a live system, and again no frame was dropped. SkyHawk is definitely a contributing factor to this success,” he concluded.