Security: video store in the storage technology (1)

Enterprise factory area increases, the requirements for security monitoring is also getting higher and higher.

Video surveillance system generally has more monitoring points, camera number, the monitoring of a long time, collecting data, time is often longer than a few days or several days. But as more and more monitoring points, video storage, it is very important.

Video surveillance application characteristics

1 digital video encoder or video server for streaming media data written to the storage device, real-time monitoring point return of image and screen to save streaming media in storage, playback workstation to stream media to read the saved video file.

This read-write mode and normal database system or file server system store small data blocks, or the file level is completely different from read-write, and so video monitoring system storage requirements in technical data and other application systems have a large difference.

2 large-scale video surveillance systems often have 2000 a 3000, even more monitoring camera, each camera generally use D1 format return images.

Each D1 image rate is 2 MB/s, all camera accumulated a total of 500 a 75OMB/S of bandwidth.

Video capture, video file formats are generally will not change, and maintains a constant bitrate, the video frame rate is generally 15 a 25 frames between the/S, that is in store for read and write operations, you must ensure that every 1/25 seconds to reach 500-75OMB/S of bandwidth, the image capture or playback occurs drop-frame, unless the storage device is configured with a large capacity of the cache.

And so video surveillance system to store not only bandwidth, requires constant bandwidth.

3 data reads and writes of long duration.

Because cameras are generally the work of 24/7, even when streaming files saved using segmentation, the duration of the write operation may take up to 2-6 hours, late playback requires the same amount of time. Therefore asked the store has a strong ability to work long hours, maintaining the stability of long time.

4 video monitoring system in General with the camera number, video image storage for a long time and therefore enormous storage capacity requirements, and as image storage time of storage capacity requirements increase linearly and explosive growth.

And so video monitoring system storage must support large capacity, and capacity with high extensibility, meet long bulk video storage needs.

5 digital video encoder typically provides standard IP interface or iSCSI interface through ADSL, LAN or on the private network, TCP/IP protocol to transmit packets of man or the iSCSI Protocol package man to return to the rear of the control center.

If the storage device has a digital video encoder with the same interface, the encoder may write data directly into the store, which will significantly reduce the supervisory system of data transmission link, provide data storage efficiency.

Video storage application storage

With a large number of video monitoring project implementation, many different types of storage is done with a video surveillance system core image data storage device.

Video surveillance system often used storage network architecture with DAS, NAS, SAN and IP-SAN, often using storage device type has a SCSI disk array, FC and iSCSI devices. These device technology is mature, simple structure, easy to implement but also installed. However, that this device has a common disadvantage of storage equipment in video surveillance system can only play a simple data-storage capabilities, irreplaceable server to run specific software applications, video monitoring systems still require considerable dedicated server.

In fact, with the rapid development of chip technology, CPU or dedicated ASIC chip operations and processing speeds doubling, and storage devices as a whole continues to lower the price.

In equipment selection and purchase, for equipment replacement, user will select a high general level of storage devices. Furthermore, when the price difference of investment sufficient time on fewer user impact. Thus in many applications, the user purchase storage device performance is often higher than the actual business system needs a lot of truth, or even exceeded several times.

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