Professional video over IP systems use some existing standard video codec to reduce the program material to a bitstream (e.g., an MPEG transport stream), and then to use an Internet Protocol (IP) network to carry that bitstream encapsulated in a stream of IP packets. This is typically accomplished using some variant of the RTP protocol.
Carrying professional video over IP networks has special challenges compared to most non-time-critical IP traffic. Many of these problems are similar to those encountered in voice over IP, but to a much higher level of engineering requirements. In particular, there are very strict quality of service requirements which must be fulfilled for use in professional broadcast environments.
Networked video is today’s generation in video surveillance and can provide numerous advantages overanalog and digital video recorder-based systems. Networked video systems (NVS) are developed to utilize Internet Protocol (IP) enabled devices, such as computers, network switches and IP cameras. Internet Protocols are a collection of standardized and globally accepted protocols for information transmission through a network. IP networks are safe and have been in use with other applications since 1974. A fi rewall, VPN (virtual private network) and password protection restrict access to data being stored and transferred. In addition, video camera manufacturers have encryption and IP fi ltering built into their cameras to help provide an added layer of protection.
Networked video systems can be smart business decisions for numerous reasons:
First, since coaxial cabling isn’t used for the connections, there may be less chance of attenuation (loss of power) due to conditions such as bending, moisture and age.
Second, a networked video system
connects via Ethernet or LAN network which typically already exists in
buildings with Internet access. It also means extra coax cable may not
have to be installed whenever newhardware is added. In cases where
additional Ethernet wiring is needed, it can be less expensive to
installand uses newer technology.
Third, the modular design of a networked video system provides business benefi ts, such as scalability and fl exibility. The entire system is built on a modular grid which helps allow for multiyear security systemexpansion plans and budgetary fl exibility.
Fourth, the use of IP technology may help minimize video network downtime by providing the option for purchasing COTS (commercial off the shelf) hardware, such as computer hard drives, servers and other components, from local computer retailers.
he functionality to manage high-traffi c times and the fl exibility to view video feeds from anywhere withan Internet connection.
A standard functionality of an NVR includes complete redundancy capabilities, which means when a server goes down, security video feeds can be redirected to a new destination server. The term “digital” is commonly used to describe functionality for both the DVR and NVR. However, it is how and where digitization is applied that is the key differentiator between the recording technologies. An NVR receives digital video feeds from cameras via an Ethernet or LAN network and uses digital technology to compress and store them on a hard drive. In contrast, a DVR receives analog video feeds via a coax cable and then uses digital technology to compress and store them on a hard drive. Therefore, on a DVR, digital technology is not used in the transmission of the images but rather only in the compression and storage of the images. In addition, because the DVR uses only its internal hard drive to compress and store video, it leaves the entire system vulnerable to a hard drive failure. This is referred to as a “single-point-of-failure” which is a common problem with single port encoder DVRs. In contrast, an IP video system is distributed across the network meaning the entire system isn’t vulnerable if something happens to the NVR. A networked video system is also an effi cient tool for managing network high-traffi c times. Networked cameras can be viewed at one rate as on a matrix system and recorded at a different rate. Simply stated, cameras can be programmed to use less of the network’s bandwidth without altering the image quality needed for viewing. In terms of security management, the Internet has dramatically changed the way owners and managers can coordinate security operational functions. The use of IP technology allows images to travel over the Internet and remain consistent, regardless of the distance traveled. This means a remote viewer can have the ability to see video of the same quality as they would if they were onsite. Networked video systems permit live video feeds, events and analytics to be viewed anywhere with an Internet connection. In turn, this provides management teams with the agility to respond faster and more effectively to security events and still have the fl exibility to leave the premises.
as the main storage component and typically has limited capacity. Video clips that are needed for
extended periods of time must manually be moved to a SAN, external hard drive or burned to a DVD. Each of these latter storage options requires personnel to handle the data transfer and can be cumbersome, time-consuming and provides fi le corruption opportunities.
Carrying professional video over IP networks has special challenges compared to most non-time-critical IP traffic. Many of these problems are similar to those encountered in voice over IP, but to a much higher level of engineering requirements. In particular, there are very strict quality of service requirements which must be fulfilled for use in professional broadcast environments.
Networked video is today’s generation in video surveillance and can provide numerous advantages overanalog and digital video recorder-based systems. Networked video systems (NVS) are developed to utilize Internet Protocol (IP) enabled devices, such as computers, network switches and IP cameras. Internet Protocols are a collection of standardized and globally accepted protocols for information transmission through a network. IP networks are safe and have been in use with other applications since 1974. A fi rewall, VPN (virtual private network) and password protection restrict access to data being stored and transferred. In addition, video camera manufacturers have encryption and IP fi ltering built into their cameras to help provide an added layer of protection.
ADVANTAGE of video over IP
I. Lower Cost of Ownership:
Networked video systems can be smart business decisions for numerous reasons:
First, since coaxial cabling isn’t used for the connections, there may be less chance of attenuation (loss of power) due to conditions such as bending, moisture and age.
Third, the modular design of a networked video system provides business benefi ts, such as scalability and fl exibility. The entire system is built on a modular grid which helps allow for multiyear security systemexpansion plans and budgetary fl exibility.
Fourth, the use of IP technology may help minimize video network downtime by providing the option for purchasing COTS (commercial off the shelf) hardware, such as computer hard drives, servers and other components, from local computer retailers.
2. “Future-Proof” IP System Technology:
Purchasing a networked video system platform can be more “future-proof” than other platforms. An IP system can be more easily upgraded because IP technology is more than just a “black box.” The IP platform is unique in permitting both software and hardware upgrades to be completed without worrying about integration issues with older cameras. Of equal signifi cance is the ability of the NVS to allow upgrades while the network is running and without the hassle of scheduling downtime for updates.The ability to upgrade software and other applications when necessary, add new hardware when needed and to integrate legacy cameras can help provide the end user with an opportunity to utilize their same video surveillance security system for many years.3. Improved Management Capabilities:
The Network Video Recorder (NVR) operates like a command center for the entire system, providing more m control and making modifi cations easier. The management capabilities of an NVR include the use of more consistent digital technology, the ability to effi ciently redirect video feeds when a server goes down,he functionality to manage high-traffi c times and the fl exibility to view video feeds from anywhere withan Internet connection.
A standard functionality of an NVR includes complete redundancy capabilities, which means when a server goes down, security video feeds can be redirected to a new destination server. The term “digital” is commonly used to describe functionality for both the DVR and NVR. However, it is how and where digitization is applied that is the key differentiator between the recording technologies. An NVR receives digital video feeds from cameras via an Ethernet or LAN network and uses digital technology to compress and store them on a hard drive. In contrast, a DVR receives analog video feeds via a coax cable and then uses digital technology to compress and store them on a hard drive. Therefore, on a DVR, digital technology is not used in the transmission of the images but rather only in the compression and storage of the images. In addition, because the DVR uses only its internal hard drive to compress and store video, it leaves the entire system vulnerable to a hard drive failure. This is referred to as a “single-point-of-failure” which is a common problem with single port encoder DVRs. In contrast, an IP video system is distributed across the network meaning the entire system isn’t vulnerable if something happens to the NVR. A networked video system is also an effi cient tool for managing network high-traffi c times. Networked cameras can be viewed at one rate as on a matrix system and recorded at a different rate. Simply stated, cameras can be programmed to use less of the network’s bandwidth without altering the image quality needed for viewing. In terms of security management, the Internet has dramatically changed the way owners and managers can coordinate security operational functions. The use of IP technology allows images to travel over the Internet and remain consistent, regardless of the distance traveled. This means a remote viewer can have the ability to see video of the same quality as they would if they were onsite. Networked video systems permit live video feeds, events and analytics to be viewed anywhere with an Internet connection. In turn, this provides management teams with the agility to respond faster and more effectively to security events and still have the fl exibility to leave the premises.
4. Reduced Bandwidth for Compression, Transmission and Storage:
For all video systems, image compression, transmission and storage require the most bandwidth. Compressing images, especially before transmission, helps minimize network bandwidth requirements, lets transmissions travel faster over a network and can allow video feeds to be stored more effi ciently. In addition, to accommodate network high-traffi c times, networked video users have the fl exibility to modify image compression specifi cations as well as size and frame rates without affecting image quality. Simply stated, when necessary, network cameras have the functionality to be viewed at one rate (30 fps NTSC/ 25 fps PAL) as on a matrix system, and recorded at a different rate (from 1-30 NTSC/1-25 PAL fps per camera). Video over IP systems use a more effective compression protocol than traditional systems. Traditional systems video is converted to digital imagery at the DVR and then compressed for storage. This means the DVR hard drive has to handle all conversions, compressions and storage. Whereas, IP-based systems distribute these functions throughout the network putting signifi cantly less stress on the recorder. In addition, some newer network cameras have built-in functionality to compress images before video feeds are released to the network. In terms of storage, IP video network storage can be more effi cient than traditional systems. As part of the NVR functionality, video feeds can automatically be moved to a storage area network (SAN) at predetermined times or manually when space is needed. In contrast, a traditional DVR hard drive servesas the main storage component and typically has limited capacity. Video clips that are needed for
extended periods of time must manually be moved to a SAN, external hard drive or burned to a DVD. Each of these latter storage options requires personnel to handle the data transfer and can be cumbersome, time-consuming and provides fi le corruption opportunities.
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