Discussion on Application of Storage Products in Security Video Field
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First, the concept of disk array
To define the concept of the disk array is a simple task, because the concept has already reached consensus. The disk array (DiskArray) is a hard disk controller to control the interconnection of multiple hard disks, so that the read and write of multiple hard disks is synchronized. , reduce errors, increase efficiency and reliability of technology. Disk array is a product with high professionalism and strict reliability requirements.
However, defining a professional disk array product will be a difficult task. In the 1990s, when it came to disk arrays, peers could define exactly what a DiskArray was. There was no professional or unprofessional problem because DiskArray itself represented a professional, special product. However, since the iSCSI, SATA, and SAS technologies have been adopted, the threshold for realizing the basic functions of the disk array has been reduced. With the widespread use of linux and the mature development of technologies such as raid, iSCSI, NFS, and SAMBA in the Linux environment, the disk array is further improved. The products are more pro-innocence, and a large number of disk array manufacturers are born, which affects the degree of specialization of disk arrays. For example, a product modified with a PC server can provide the function of a disk array, and the disk array of the PC server architecture will lower the price of the product, but the reliability will not be guaranteed.
So, what is a professional disk array? Professional disk array mainly has the following hallmark features: (1) modular design, including cooling system, power supply system, data processing core system; (2) controller architecture can provide redundancy I controller configuration; (3) disaster recovery technologies such as snapshots, volume mirroring, and remote replication; (4) using independent hardware chips to solve the raid operation problem; (5) using high-performance cache technology, with cache mirroring.
Second, the development of the disk array and video surveillance market
When it comes to disk arrays, we must think of these concepts: DAS\NAS\SAN. These products have been used for years in various industries and have been used in the security monitoring industry for quite some time.
From the point of view of the development status of the entire industry, choosing a storage device with high reliability and good stability is a problem that must be considered by each program user and every plan designer. It is also a solution to success or stability. The key factor.
Recently, disk arrays that are most exposed to practitioners in the industry are generally referred to as IP SAN devices. With the development of technology, the technical threshold for implementing IPSAN is decreasing, resulting in many low-end entry-level products flooding the entire market. However, genuine professional products are not used in the industry due to price factors or unfamiliarity with the security market. People are familiar with it.
So, how to choose the products that meet the requirements from the many brands that are mixed with each other? In fact, it is very simple. In the field of data storage, the controller architecture products are very mature and stable, but they are not well known in the field of security monitoring. The product of the controller architecture meets the requirements of data preservation for security, stability, and reliability. Select this direction, and then combine the brand, price, etc. to choose. Professional disk array manufacturers will also face difficulties in entering the security market.
[NextPage] First, the industry application program is not familiar with. If you only sell equipment alone, I think it is not attractive for customers. The professional focus of professional disk array vendors is not in the security market, and the understanding of security is not deep enough. Therefore, it is not possible to directly enter the singles. The second is price difficulties. Security market, the budget is still relatively tight, and most of them have to invest in front-end construction, coupled with the lack of attention to data security, leading to a serious shortage of storage equipment procurement budget, unable to purchase high-end professional products. Therefore, it can be predicted that from now on, for a period of time, the probability of high-end professional storage brands appearing frequently in security monitoring projects is not great.
This kind of situation is actually a good opportunity for practitioners in the security industry, whether it be from the trend of technological development or from the stimulation of market demand, or from the integrity and reliability of the overall solution. , should guide customers to choose stable and reliable products.
Taking UOB as an example, in 2012, it will launch a series of high-reliability professional disk arrays and adopt a controller architecture to ensure the stable operation of the equipment from the overall structure and provide reliable protection for customer data security.
Disk arrays address not only the problem of storage space, but also the responsibility for the security of stored data. Now many entry-level low-end products on the market use PC server architecture and general-purpose industrial control chassis. Using linux open-source raid management software and iSCSItarget, the basic "save" function is solved. The price is also very advantageous, but the disadvantages are obvious. Failure recovery will be powerless. Using this solution, post-maintenance will cause great confusion for customers: Can these disk arrays work stably?
Professional disk array products ensure the security of stored data from many aspects. First, it must be a device with no single point of failure. It must be a device with no internal cable connection. It must be a modularly designed device. This ensures the stability and reliability of the device from the hardware. Secondly, it must implement internal path multipath switching and load balancing. It must support external path multipath switching and link aggregation. It must support advanced backup functions such as snapshot, volume mirroring, data migration, and remote replication. Software features can be used to protect user data from high availability.
At present, most of the professional disk array products, measured from the use rate, the average annual downtime will not be greater than 0.05%, that is, the annual reliability of 99.95%, conversion, down time is not more than 5 hours, and Some high-end products achieve an annual utilization rate of 99.99%, and the average annual downtime will not exceed 57 minutes.
Third, the analysis of several professional storage solutions
In the field of professional storage products, we can't talk about DVRs or NVRs in the surveillance area because they are not a concept at all. However, in the security field, they are targeting different projects with NAS, DAS, SAN, and so on. Come to different choices.
Next, for the difference of the monitoring system, we will subdivide the best application program in various systems.
1. Small-scale monitoring system
The small-scale monitoring system is mainly based on analog cameras + embedded DVR equipment or NVR + IPC equipment such as the district, school district and other monitoring applications. In these environments, we can use cost-effective, stable devices for data storage protection. In general, in these applications, embedded DVRs and NVRs can use their own multiple hard drives for data storage. In this case, the number of monitoring points is generally within 50 points. Using the embedded DVR's own storage capacity can fully meet the needs of the application.
2. Medium-sized application monitoring system
In this kind of application, the number of monitoring points is generally around 500 points, and the storage time is long. Usually, the real-time 24-hour recording strategy is also adopted. Therefore, a large amount of data is generated, and the storage requirements are relatively high. Further improvements in control, management, and other requirements.
[NextPage] In this application environment, we generally recommend the use of IPSAN with the coding device + video synthesis platform for data storage, the advantage of this is that users can conduct unified management of the device, centralized storage of data, management and data Security has been greatly improved. In this scheme, the storage space required by the data is considerable. How to effectively store data and how to safely and reliably ensure that these data are not lost? Choosing a stable and reliable product will reduce many unnecessary tasks for later maintenance work. trouble.
3. Large-scale application monitoring system
In general, large-scale monitoring systems can reach more than a thousand points. The most typical case is Safe City. The biggest feature of this type of application is that the system is large, complex, and has a large amount of data. Most of the applications will adopt a tiered storage and central centralized backup strategy. The performance and stability of data storage devices are more stringent. The security of the monitoring center is more secure. Concern, therefore, there will be the coexistence of IPSAN and FCSAN.
As the first-level storage, IPSAN bears all the storage pressures of each sub-control center, and also uploads important data to the upper-level data center for backup. In addition to the stability and reliability of the product requirements, the IPSAN must be considered. But also have higher requirements for the product's reading and writing capabilities. As a sub-central storage device, it may also need to consider the overall cost. Compared with other network storage products, IPSAN is the best choice for this occasion. Both in terms of cost performance and device adaptability, it can meet the requirements of the center.
The choice of FC SAN as a primary data center storage device takes into account that the device can provide more reliable service quality and better delay characteristics of fiber links, and solve the network bottleneck caused by large data throughput.
IV. Analysis of Application Situation of Storage Products in Security Video Field
With the rapid development of the security industry, people are paying more and more attention to the storage and security of data. Compared with financial data storage, medical center data storage, Internet center business data storage and other fields, the security market for data security considerations is not ranked in the forefront of all needs, many projects only require survival, with basic security , Does not consider the follow-up fault recovery, data backup and other needs, in the event of a failure, it is extremely difficult to ensure data security. However, with the development of high-definition video technology and the reduction in the overall cost of high-definition projects, high-definition applications are becoming more widespread, and people will inevitably attach importance to data security. Due to the video quality problems of previous video materials, most of these video materials are only used as a reference for ex post facto evidence collection. They are not necessarily required. In addition, the industry has a higher cost requirement for project construction, which directly leads to the application of the entire security monitoring industry. Centralized storage devices are relatively low-end. Pursue price, do not pay attention to equipment stability; only pay attention to storage space, do not pay attention to equipment grade. All these have caused the low end of the data storage equipment requirements of the security video surveillance industry. It can be said that the security and stability requirements of the security monitoring industry are all at the end of the entire storage industry. The arrival of the era of high-definition will completely change this pattern. Because high-definition video can see more details and cover a wider space, it can better support video intelligent analysis technology for later excavation work, which means that the reference value of video data is greatly improved, from a kind of dispensable. The status is directly elevated to an important position that must be referenced. As the importance of data increases, data security will also increase several levels.
V. Conclusion
In recent years, security video surveillance technology is constantly seeking breakthroughs, not only upgrading the technology itself, but also constantly seeking to introduce mature technologies from other industries. In the security video surveillance industry, we recently saw a reference to the HD-SDI technology in the broadcasting industry. Going forward, we have expanded our business to Ethernet to enable centralized monitoring, networked applications, and more. All these prove that as long as there are application requirements, they can learn from and digest advanced technologies from other industries and improve the overall solution.
At present, the security and reliability of storage devices have become a common concern in the industry. Therefore, we can fully introduce the mature technologies of the data professional storage industry, draw on their advanced concepts, improve the problems of centralized storage in security video surveillance solutions, and even optimize the specificity of data reading and writing in the video surveillance industry. Out of professional products that meet industry applications. 
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