Security Industry Storage Mainstream Technology Analysis

During the development of security day and night, or for a long time in the future, which kind of storage technology will lead the tide, what are the current mainstream technologies in the market? This article answers your questions.

Security Storage Requirements First, security storage needs for mass storage. The monitoring data is written in 7×24 hours and stored for 7 days and 15 days. . . . . . Even up to a year, the amount of data increases linearly with time. For a safe city project, the total number of monitored routes is usually several thousand to tens of thousands of roads. Thousands of terabytes of projects are common, which is unimaginable for the traditional storage industry.

Second, performance requirements. Video surveillance is primarily the writing of video streams, and the performance of the representation is the number of streams that the storage can support (usually 384Kbps-2Mbps). In the case of multi-channel concurrent writes, there is a large impact on bandwidth, data capacity, cache, etc., and there is a great deal of pressure on storage. At this time, storage needs to be optimized for video performance.

Third, the sensitivity of security storage prices. Security monitoring industry's mass storage, due to the large total capacity, caused an increase in the total price cost. Conversely, the unit cost of capacity (per TB price) is very high.

Fifth, centralized management requirements. In the security monitoring application, since a large amount of storage devices and massive data in the storage devices are needed, they must be managed effectively and provide convenient, reliable, and transparent support for the use of end users.

Finally, networking requirements. TCP/IP network is the network foundation for the development of security monitoring technology in the direction of networking. Storage technology based on TCP/IP network will play an irreplaceable role in the security monitoring technology network process.

Based on the above understanding of the application, the storage gives us a conclusion worthy of learning: Security storage in the monitoring field may develop in two major areas, one for small and medium-sized applications where the node is not too much, the NVR is the main development direction in the future; Followed by a large-scale monitoring system, video management platform + SAN storage (based on ISCSI storage) is still the best choice for large-scale monitoring systems.

Security storage technology 1, DVR storage. DVR storage is currently the most common storage mode. The codec device directly connects the hard disk. Currently, up to 8 hard disks are available. However, due to the performance limitations of the codec equipment, the hard disk sequential write mode is generally adopted, and RAID redundancy technology is not used to implement data protection. With the continuous increase in the capacity of hard disks, the probability of failure of key data due to the failure of a single hard disk is increasing at the same time, and the limitations of DVR performance also affect the sharing and analysis of image data. The characteristics of this method are: cheap, easy to use, can be operated through the remote control and keyboard; DVR is suitable for small-scale, distributed deployment. Domestic DVR products such as Haikang, Dahua's products are already very mature.

2. The encoder is directly connected to the storage. The codec external storage device is connected through the external storage interface of the codec, and mainly uses storage protocols such as SATA, USB, iSCSI, and NAS. In this way, the re-expansion of the codec capacity can be achieved, which is suitable for the deployment of small and medium-scale security storage. The reliability of monitoring video data through RAID technology is guaranteed.

The direct connection mode adopted by the SATA/USB mode cannot be shared and the expansion capability is low. The current application is gradually being eliminated; the IP network (iSCSI and NAS) modes have better expansion capabilities and sharing capabilities. For example, a series of network storage products can directly write video data to a number of mainstream manufacturers' encoding devices, which reduces the number of server relays and saves the user's investment while improving performance. However, this method requires Rely on the streaming media server for data forwarding and retrieval, it is easy to have a bottleneck in streaming media forwarding. At present, direct write usually uses NAS storage. Due to the NAS's own file protocol and other reasons, it causes multiple nodes to concurrently write data. low efficiency.

3, centralized storage. The server connects to the front-end codec, downloads the data through the streaming media protocol, and stores it on the storage device. Servers and storage devices can be connected through SAS, iSCSI, NAS, and FC protocols. The centralized storage method is suitable for the deployment of large and medium-sized platforms. Among the centralized storage methods, the IP connectivity mode (iSCSI) and the FC connection mode have good scalability and manageability, and are currently one of the most widely adopted methods. From the perspective of actual deployment and effect, FC storage is more suitable in the monitoring environment with more nodes due to its powerful performance and data processing capabilities. IP storage can be implemented in small and medium-sized applications due to limitations in performance and scalability. High cost performance.

4, NVR storage. In the video surveillance system, NVR is an ideal upgrade product for analog video recorders and hard disk video recorders. It is a stand-alone operation device that is based on the original DVR and eliminates the need for Windows operating systems and computers to work together. Because NVR adopts highly integrated chip technology, it possesses advanced digital video recording, storage and playback functions, no need to replace and store video tapes, and does not require computer coordination and routine maintenance. Therefore, it can achieve high resolution (full-D1 resolution can be achieved). Rate), high quality real-time monitoring, and easy to use. In simple terms, the security storage of the NVR system digitizes the traditional video, audio and control signals, and transmits them on the network in the form of IP packets through the network interface on the NVR device. On the basis of the DVR, the system is networked. .

In the application, although the NVR system has the advantages of computer's fast processing capability, digital information anti-jamming capability, convenience of quick query recording, clear video images, and multiple display of stand-alone images. However, in essence, NVR not only fails to solve the problem of analog transmission existing in DVR system, but also does not solve the more management problems brought by network transmission of video stream. In fact, each NVR forms an independent monitoring center, which brings more complexity to the realization of the whole network monitoring. In areas such as remote control, multi-level scalability, and networking capabilities, there is still room for improvement.

Video application storage characteristics In some small and medium-sized video surveillance systems, the performance bottleneck in the system often appears on the video server rather than on the storage device. The bandwidth that the storage device can provide is often twice or three times the actual total bandwidth of video surveillance. IOPS is about 3-5 times of actual demand. The storage device controller is in a half-load working state for a long time, and a large amount of high-performance resources are wasted.

To ensure high availability, high efficiency, stability, and security, the controller part of the storage device is generally designed specifically and uses dedicated processors and caches. Its technical parameters and performance are higher than those of ordinary PC servers. In order to effectively use the stored extra resources, application software with special functions can be embedded in the controller of the storage device. The storage device not only provides a data storage server for the system, but also provides a certain software application server. Such a storage device is called For application storage.

Application Storage Architecture For video surveillance network storage systems, application storage devices are a new type of high-performance storage device with media management and dedicated software application capabilities.

Compared with ordinary storage, application storage has the functions of network management, media asset management, video transcoding, video on demand, and storage sharing management in addition to basic data storage and security protection.

Application storage means that when the performance provided by the storage device itself exceeds the system requirements, the high reliability and stability of the storage device are used to run certain application software services on the storage. Contrary to common storage devices, application storage will change the architectural design of many application systems in addition to adding many software applications and service functions.

Storage devices are generally designed based on the principles of modularity, redundancy, and hot-plugging. They eliminate internal single-point failures, and their security and stability far exceed the common PC servers used in the system. Application software And the internal storage of the server can provide the system with higher stability and system security.

Efficient: The core of the storage device, the controller, generally uses a specially designed bus structure, a dedicated processing chip, and a cache, optimized for data verification and data transfer. Under long-term operation conditions, application storage can not only ensure the security and stability of software and server functions, but also ensure higher running and computational efficiency than ordinary PC servers, and can provide a higher service quality for the system.

System architecture is simple: Due to many software applications and service functions centralized in the application storage, a large number of PC servers and connected network connection devices and network interface cards can be saved in the system architecture design, which greatly simplifies the system architecture. . The simplification of the system structure makes use of the workflow of optimizing the system and improves the system's operating efficiency. At the same time, due to the reduction of the type and quantity of equipment required by the system, the construction cost of the system can also be greatly reduced.

Save bandwidth: If you use application storage, video transcoding or other software or services run on the application storage device. During the entire process of transcoding video files, data is transmitted only between the controller and disks inside the storage device. No external server is required. Participation also requires no network equipment for transmission and switching, and thus does not require the bandwidth of the network system. External servers and workstations can get more network data for other operations.