In the security industry, there has been a popular saying that 2010 is the first year of high-definition eruption, and 2011 is the year of full-scale entry into HD. According to the performance of the security market in 2010, whether it is the enthusiasm of manufacturers for high-definition products, or the expectations and doubts of high-end products from user engineering firms, HD seems to have come to us.
It should be said that the rise of the digital high-definition network video surveillance market has not only stimulated the huge demand for digital HD network cameras, but also stimulated the storage device market. Relevant data show that when traditional DVR and NVR solutions are used, the cost of storage equipment accounts for approximately 15% to 30% of the entire video surveillance system; and in the digital network high-definition video surveillance system, the cost of storage devices in the entire system It will rise to 50% to 70%.
With the continuous expansion of the megapixel digital high-definition network video surveillance market, more and more end-users tend to use digital and network video recorders to store and retrieve surveillance video, and mega-pixel cameras produce lower-resolution video data. There are many more cameras and it is a major challenge to build surveillance storage solutions.
Characteristics of Security Surveillance Storage The main feature of video surveillance systems is the large amount of image information and requires sufficient storage space. Unlike other types of systems, video surveillance systems generally have many features such as multiple monitoring points (large number of cameras), large video data streams, long storage time, and continuous 24-hour operation.
Taking the most basic HD 720P effect as an example, the hard disk capacity required for normal surveillance video is approximately 4G to 8G/line•hour. For economical reasons, reducing the hourly video recording can be reduced to about 3GB. Taking this as an example, eight-way monitoring is about 17T (17000G) capacity, based on one-month retention time.
One can imagine that if you need hundreds of thousands of such high-definition monitoring, such a huge video data on the storage device capacity, read and write performance, reliability put forward higher requirements. Specifically, the requirements for storage devices for video surveillance applications are as follows:
1. Video data is written to or read back from the storage device in streaming media, which is different from traditional file reading and writing.
2. Multi-channel video writes to the same storage device for a long time, requiring the storage system to work stably for a long time.
3. Real-time multi-channel video writing requires the storage system to have high bandwidth and constant.
4. The huge capacity requirements and high storage expansion performance require online replacement of faulty devices or capacity expansion.
5. Multiple concurrent reads and writes require very high performance for storage devices.
It should be said that as a carrier of image data and alarm event records, the importance of storage is self-evident. Currently, storage is not only a device but has been sublimated to a solution platform. A large-capacity storage system is not a simple accumulation of storage devices. It also needs to address the completeness of storage mechanisms, storage standards, and availability in terms of time (storage data processing speed) and space (storage capacity). Capacity management system manageability requirements.
Currently, the main methods for monitoring storage are along with the development of storage technologies, and the storage methods of the video surveillance industry are constantly evolving. Currently, security monitoring and storage are mainly in the following four ways:
DVR storage. In the late 1990s, digital video surveillance based on digital signal processing (DSP) gradually began to gain popularity. Various types of codec technologies were widely used in image processing, and processed images could also be transmitted as digital code streams. The storage also began to enter the digital era. The most typical application is a Digital Video Recorder (DVR), which uses an internal hard disk for image storage.
DVR storage is currently the most common storage mode. The codec device directly connects the hard disk and can directly bring up to 8 hard disks. Due to the limitation of the performance of the encoding and decoding equipment, the hard disk sequential write mode is generally used, and RAID redundancy technology is not used to implement data protection. With the ever-increasing hard disk capacity, the chance of a single-disk failure causing the loss of critical data is increasing at the same time. With the continuous development of remote video surveillance, DVR storage also shows obvious front-end and stand-alone features.
NVR storage. NVR (Network Video Recorder) is a product form that has gradually emerged in China's security market in the past two years. In the video surveillance system, NVR is an upgraded product of analog video recorders and hard disk recorders. It is based on the original DVR. Exempts the standalone operating device that the window operating system and the computer cooperate with. Because NVR adopts highly-integrated chip technology and possesses advanced digital video recording, storage, and replay functions, it does not require computer cooperation and routine maintenance. Therefore, it can achieve higher resolution (up to D1 resolution) and high-quality real-time monitoring. And easy to use.
In simple terms, the NVR system digitizes 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. The NVR is based on a large system and networked design. The business may be "data center", and the management is based on the idea of ​​the console. If necessary, such a system can also use network storage for backup.
The encoder plug-in storage device is directly connected to the storage. Connected via the external memory interface of the codec, it mainly uses storage protocol extensions such as SATA, USB, iSCSI, and NAS. In this way, the re-expansion of the codec capacity can be achieved, which is suitable for small-to-medium-scale deployments. Monitoring video data is assured in terms of reliability through RAID technology. Among them, the direct connection method adopted by the SATA/USB mode cannot be shared and has low expansion capability. IP network (iSCSI and NAS) modes have better scalability and sharing capabilities. Because of the direct writing of data, this step of server relay is reduced, and the user's investment is saved while the performance is improved. However, in this method, it is easy to perform a large bottleneck in the forwarding process during data forwarding and retrieval. At present, direct writes generally use a storage method such as a NAS. Due to the NAS's own file protocol, etc., it is not efficient to concurrently write data in multiple nodes.
Centrally manage 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. In terms of actual deployment and effect, FC storage is more suitable in a node-rich monitoring environment due to its powerful performance and data processing capabilities. IP storage can be more suitable for small and medium-sized applications due to limitations in performance and scalability. High cost performance.
At present, many manufacturers have developed DVRs or NVRs with networking transmission capabilities, as well as NAS and SAN hardware and software devices with network storage architectures. From the actual situation, NAS adopts disk arrays and network architectures with large storage capacity, and SAN cooperates with the monitoring and management platform to provide more storage space, with easy storage space expansion, flexible addressing, and long-distance data transmission. High storage device utilization, suitable for large-scale centralized network monitoring system. IPSANs are currently a hot spot in the video surveillance storage market, and DVRs will coexist with other storage methods for a long period of time.
Cloud storage - the trend of future development?
In the past two years, Telecom and China Netcom have built a number of "global eye" and "wide-view" network video surveillance systems of different scales across the country. The ultimate goal of the “Global Eye†or “Wide Horizon†system is to build a nationwide video surveillance system similar to that of voice networks and data services networks, providing remote users with real-time video monitoring and video playback capabilities and through services. To collect fees. However, due to the limited network conditions within the city and between cities, and the limitation of the scale of storage equipment for video surveillance systems, the “global eye†or “wide-view†can generally only be built within a city.
Taking the construction of a safe city as an example, the networking requirements of thousands of camera video recordings can be achieved without the addition of simple storage devices. Still 720P high-definition camera mentioned above as an example, its hourly video recording can be compressed to about 3GB capacity, according to the monthly storage time requirements, can get such a data: 3GB/hour × 24 hours × 30 days × 1 Road =2.16T. The current number of large-scale network surveillance cameras in Ping'an City is as low as several hundred, and as many as tens of thousands. Assume that a traffic monitoring system has 500 high-definition cameras. The minimum storage capacity required for a 30-day monitoring system is 1 PB. The province's traffic monitoring system is networked, and if the national traffic monitoring network? It can be imagined that such a huge amount of data storage has to be a challenging problem for the storage industry.
Cloud computing is a hot topic in IT circles in the past two years. The concept of cloud storage extended and developed in the concept of cloud computing is extremely attractive to the storage industry. It is applied to cluster applications, grid technologies, or distribution. The functions of the file system, etc., bring together a large number of different types of storage devices in the network to work collaboratively through application software, and provide external data storage and service access functions. It seems that the large-scale networked video surveillance systems have brought a dawn.
However, just as the cloud computing has brought troubles to IT industry personnel, the concept of cloud storage seems to face many problems that must be solved, such as data security, data transmission delay, storage portability and other issues.
Data security. Since the birth of cloud computing, security has always been a controversial topic. Similarly, in terms of cloud storage, security is usually the primary business consideration and technical consideration. The security of video surveillance data can be imagined, how to meet the user's requirements for data security is probably the reality that cloud storage has to face.
Data transmission delay. One of the difficulties that remote video surveillance can't avoid is monitoring the delay of recording. Especially when a major emergency occurs, it is very likely that a one-second delay will result in significant loss of human and financial resources. So, how does cloud storage ensure sufficient access to the crowd in the case of large-scale data requests?
Storage portability. Some users also need to consider the portability of data when considering hosted storage. This is generally guaranteed, and some large service providers offer solutions that promise data portability comparable to the best of traditional local storage. Some cloud storage combines powerful portable features that can deliver the entire data set to any media of your choice, even to specialized storage devices.
Conclusion: Once, DVR took the lead in storage in the security field for a long time. At present, it is still one of the most common modes of security storage. However, under the digital digital video surveillance system, the current integrator With more choices, storage solutions such as NAS, iSCSI, and FCSAN appear to be more popular - NAS solutions facilitate the sharing of storage information, iSCSI and FC SAN solutions facilitate the expansion of storage capacity; embedded NVRs do not have the cost due to comparison Competitiveness is used less often. With the high-definition, networking, these words continue to impact the field of video surveillance, existing storage methods do not seem to solve the problem of mass data storage, the emergence of cloud storage, can bring security to the security industry it?
It should be said that the rise of the digital high-definition network video surveillance market has not only stimulated the huge demand for digital HD network cameras, but also stimulated the storage device market. Relevant data show that when traditional DVR and NVR solutions are used, the cost of storage equipment accounts for approximately 15% to 30% of the entire video surveillance system; and in the digital network high-definition video surveillance system, the cost of storage devices in the entire system It will rise to 50% to 70%.
With the continuous expansion of the megapixel digital high-definition network video surveillance market, more and more end-users tend to use digital and network video recorders to store and retrieve surveillance video, and mega-pixel cameras produce lower-resolution video data. There are many more cameras and it is a major challenge to build surveillance storage solutions.
Characteristics of Security Surveillance Storage The main feature of video surveillance systems is the large amount of image information and requires sufficient storage space. Unlike other types of systems, video surveillance systems generally have many features such as multiple monitoring points (large number of cameras), large video data streams, long storage time, and continuous 24-hour operation.
Taking the most basic HD 720P effect as an example, the hard disk capacity required for normal surveillance video is approximately 4G to 8G/line•hour. For economical reasons, reducing the hourly video recording can be reduced to about 3GB. Taking this as an example, eight-way monitoring is about 17T (17000G) capacity, based on one-month retention time.
One can imagine that if you need hundreds of thousands of such high-definition monitoring, such a huge video data on the storage device capacity, read and write performance, reliability put forward higher requirements. Specifically, the requirements for storage devices for video surveillance applications are as follows:
1. Video data is written to or read back from the storage device in streaming media, which is different from traditional file reading and writing.
2. Multi-channel video writes to the same storage device for a long time, requiring the storage system to work stably for a long time.
3. Real-time multi-channel video writing requires the storage system to have high bandwidth and constant.
4. The huge capacity requirements and high storage expansion performance require online replacement of faulty devices or capacity expansion.
5. Multiple concurrent reads and writes require very high performance for storage devices.
It should be said that as a carrier of image data and alarm event records, the importance of storage is self-evident. Currently, storage is not only a device but has been sublimated to a solution platform. A large-capacity storage system is not a simple accumulation of storage devices. It also needs to address the completeness of storage mechanisms, storage standards, and availability in terms of time (storage data processing speed) and space (storage capacity). Capacity management system manageability requirements.
Currently, the main methods for monitoring storage are along with the development of storage technologies, and the storage methods of the video surveillance industry are constantly evolving. Currently, security monitoring and storage are mainly in the following four ways:
DVR storage. In the late 1990s, digital video surveillance based on digital signal processing (DSP) gradually began to gain popularity. Various types of codec technologies were widely used in image processing, and processed images could also be transmitted as digital code streams. The storage also began to enter the digital era. The most typical application is a Digital Video Recorder (DVR), which uses an internal hard disk for image storage.
DVR storage is currently the most common storage mode. The codec device directly connects the hard disk and can directly bring up to 8 hard disks. Due to the limitation of the performance of the encoding and decoding equipment, the hard disk sequential write mode is generally used, and RAID redundancy technology is not used to implement data protection. With the ever-increasing hard disk capacity, the chance of a single-disk failure causing the loss of critical data is increasing at the same time. With the continuous development of remote video surveillance, DVR storage also shows obvious front-end and stand-alone features.
NVR storage. NVR (Network Video Recorder) is a product form that has gradually emerged in China's security market in the past two years. In the video surveillance system, NVR is an upgraded product of analog video recorders and hard disk recorders. It is based on the original DVR. Exempts the standalone operating device that the window operating system and the computer cooperate with. Because NVR adopts highly-integrated chip technology and possesses advanced digital video recording, storage, and replay functions, it does not require computer cooperation and routine maintenance. Therefore, it can achieve higher resolution (up to D1 resolution) and high-quality real-time monitoring. And easy to use.
In simple terms, the NVR system digitizes 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. The NVR is based on a large system and networked design. The business may be "data center", and the management is based on the idea of ​​the console. If necessary, such a system can also use network storage for backup.
The encoder plug-in storage device is directly connected to the storage. Connected via the external memory interface of the codec, it mainly uses storage protocol extensions such as SATA, USB, iSCSI, and NAS. In this way, the re-expansion of the codec capacity can be achieved, which is suitable for small-to-medium-scale deployments. Monitoring video data is assured in terms of reliability through RAID technology. Among them, the direct connection method adopted by the SATA/USB mode cannot be shared and has low expansion capability. IP network (iSCSI and NAS) modes have better scalability and sharing capabilities. Because of the direct writing of data, this step of server relay is reduced, and the user's investment is saved while the performance is improved. However, in this method, it is easy to perform a large bottleneck in the forwarding process during data forwarding and retrieval. At present, direct writes generally use a storage method such as a NAS. Due to the NAS's own file protocol, etc., it is not efficient to concurrently write data in multiple nodes.
Centrally manage 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. In terms of actual deployment and effect, FC storage is more suitable in a node-rich monitoring environment due to its powerful performance and data processing capabilities. IP storage can be more suitable for small and medium-sized applications due to limitations in performance and scalability. High cost performance.
At present, many manufacturers have developed DVRs or NVRs with networking transmission capabilities, as well as NAS and SAN hardware and software devices with network storage architectures. From the actual situation, NAS adopts disk arrays and network architectures with large storage capacity, and SAN cooperates with the monitoring and management platform to provide more storage space, with easy storage space expansion, flexible addressing, and long-distance data transmission. High storage device utilization, suitable for large-scale centralized network monitoring system. IPSANs are currently a hot spot in the video surveillance storage market, and DVRs will coexist with other storage methods for a long period of time.
Cloud storage - the trend of future development?
In the past two years, Telecom and China Netcom have built a number of "global eye" and "wide-view" network video surveillance systems of different scales across the country. The ultimate goal of the “Global Eye†or “Wide Horizon†system is to build a nationwide video surveillance system similar to that of voice networks and data services networks, providing remote users with real-time video monitoring and video playback capabilities and through services. To collect fees. However, due to the limited network conditions within the city and between cities, and the limitation of the scale of storage equipment for video surveillance systems, the “global eye†or “wide-view†can generally only be built within a city.
Taking the construction of a safe city as an example, the networking requirements of thousands of camera video recordings can be achieved without the addition of simple storage devices. Still 720P high-definition camera mentioned above as an example, its hourly video recording can be compressed to about 3GB capacity, according to the monthly storage time requirements, can get such a data: 3GB/hour × 24 hours × 30 days × 1 Road =2.16T. The current number of large-scale network surveillance cameras in Ping'an City is as low as several hundred, and as many as tens of thousands. Assume that a traffic monitoring system has 500 high-definition cameras. The minimum storage capacity required for a 30-day monitoring system is 1 PB. The province's traffic monitoring system is networked, and if the national traffic monitoring network? It can be imagined that such a huge amount of data storage has to be a challenging problem for the storage industry.
Cloud computing is a hot topic in IT circles in the past two years. The concept of cloud storage extended and developed in the concept of cloud computing is extremely attractive to the storage industry. It is applied to cluster applications, grid technologies, or distribution. The functions of the file system, etc., bring together a large number of different types of storage devices in the network to work collaboratively through application software, and provide external data storage and service access functions. It seems that the large-scale networked video surveillance systems have brought a dawn.
However, just as the cloud computing has brought troubles to IT industry personnel, the concept of cloud storage seems to face many problems that must be solved, such as data security, data transmission delay, storage portability and other issues.
Data security. Since the birth of cloud computing, security has always been a controversial topic. Similarly, in terms of cloud storage, security is usually the primary business consideration and technical consideration. The security of video surveillance data can be imagined, how to meet the user's requirements for data security is probably the reality that cloud storage has to face.
Data transmission delay. One of the difficulties that remote video surveillance can't avoid is monitoring the delay of recording. Especially when a major emergency occurs, it is very likely that a one-second delay will result in significant loss of human and financial resources. So, how does cloud storage ensure sufficient access to the crowd in the case of large-scale data requests?
Storage portability. Some users also need to consider the portability of data when considering hosted storage. This is generally guaranteed, and some large service providers offer solutions that promise data portability comparable to the best of traditional local storage. Some cloud storage combines powerful portable features that can deliver the entire data set to any media of your choice, even to specialized storage devices.
Conclusion: Once, DVR took the lead in storage in the security field for a long time. At present, it is still one of the most common modes of security storage. However, under the digital digital video surveillance system, the current integrator With more choices, storage solutions such as NAS, iSCSI, and FCSAN appear to be more popular - NAS solutions facilitate the sharing of storage information, iSCSI and FC SAN solutions facilitate the expansion of storage capacity; embedded NVRs do not have the cost due to comparison Competitiveness is used less often. With the high-definition, networking, these words continue to impact the field of video surveillance, existing storage methods do not seem to solve the problem of mass data storage, the emergence of cloud storage, can bring security to the security industry it?
Metal Wire,Fence,Wire Mesh Co., Ltd. , http://www.nsmeshmetals.com