Fundamentals of designing and deploying a Video Surveillance System

There are eight essential questions which have to be answered when you embark on your project of designing a video surveillance system. Here is an in-depth analysis meant for beginners, to understand the options and substitutes available to design a robust surveillance system.

The 8 essential questions which need to be sorted out are

1.)    What type of surveillance cameras should be used?

2.)    How to connect the cameras with the VMS?

3.)    What type of video management system should be finalized?

4.)    What type of video storage must be used?

5.)    What type of video recording must be selected?

6.)    Do I need Video Analytics?

7.)    How to view and record the surveillance video?

8.)    Do I need to integrate videos surveillance with access control systems?

1.) Surveillance cameras- Video Surveillance cameras are meant to be an essential component of a Video Surveillance System. In order to capture the right events in the right way, it becomes essential to deploy surveillance cameras in right and critical areas. The right place to deploy the surveillance cameras is where people or objects enter/exit, also known as chokepoints. Examples for chokepoints are doorways, hallways, driveways, corridors and gate ways. The deployment of cameras at entry/exit points will offer evidence on who entered the facility and at what time and date. In order to capture assets/objects, the cameras need to be deployed in areas where full view of objects/assets can be gained with clarity. For instance, placing cameras at the cash counter of a shopping mall will facilitate documentation of transactions taking place at the counter.

Once the area of deployment is confirmed then comes the turn of figuring out the right camera variant. Depending upon the application needs, a fixed or a PTZ camera can be selected. If the application need is simple monitoring of place or object then fixed camera can be the right option. With the present day advanced technology in place, clarity filled images/videos of the monitoring area can be easily gained. If the application need is to monitor moving objects/people then the need for PTZ camera arises. PTZ cameras facilitate panning, zooming and tilting of the camera to achieve wider fields of view. Usually, fixed cameras are almost 5-8 times less costly than PTZ cameras.

Color/ IR/ Thermal cameras- Depending upon the monitoring needs a camera with Infrared or thermal capabilities is selected. IR cameras use special lamps to make the image clear in zero light conditions, in order to capture an image. Thermal cameras are usually preferred for long range surveillance environments, where motion detection is sufficient. Obviously, if the application demands for color images, color surveillance cameras are preferred and prove beneficial in many instances. Like for instance, if a person wearing dark glasses and a red T-shirt has to be identified from among a crowd, a camera with color variant has the capability to do so. However, the deployment of colored cameras becomes suitable when the surveillance environment has well lit conditions.

Megapixel cameras or Standard Definition cameras- It’s like a similar situation where the choice has to be made between an LCD TV and a Smart TV. Obviously, both produce the same content under normal circumstances. But it is the clarity and picture quality which differentiates the two in the consumer’s world. Similarly, people used to use standard definition cameras for their surveillance needs. But now the technology is far more advanced and now users can choose high definition camera which facilitate clarity filled high definition images.

The other point which is important while selecting a surveillance camera is decision between IP and Analog technology. Presently, the on-going trend is to shift from analog cameras to IP cameras, as the later mode of surveillance brings in a bouquet of benefits. The intelligence to digitalize the image inside the network camera is making users shift to IP surveillance; where as Analog surveillance doesn’t serve this purpose.

Nowadays, in most surveillance environments a mix-up of surveillance camera types is seen in practice and moreover budget also plays a criterion in selection for analog or IP camera deployment.

2.) Connectivity- As discussed in earlier paragraphs, video can be transmitted over IP or as a native LAN network. However, most of the video feeds are being sent on IP network these days and so the craze for network cameras is increasing, as they can be directly connected to an IP network layout. In an analog system, cameras have to be first connected to a Digital Video Recorder and from that point then can be interfaced with the web. Yes, there is also an encoder option available for the analog cameras to connect to IP network.

Now, the situation arises on how to connect the cameras as captured videos. Irrespective of an IP or an Analog camera usage, the video feeds captured by these devices can be sent through cables or wires these days.

Sending videos via cable is still popular in most of the surveillance environments, as it offers highest point of security in doing so. Seventy percent of surveillance camera deployments are being made on cable layout. When the feasibility to lay cables becomes zero, then the option of using wireless transmission arises. But here, the chances of intercepting the signals and manipulating the videos can come up. Conversely with the latest technological advancements taking place in wireless transmission, the chance of signal interception is getting decreased.

3.) Video Management System- Video Management System is where all the intelligence of the surveillance system is contained. It acts as a hub, where functions such as acceptance of video from surveillance cameras, storing of the videos and managing the viewing for users, are resided. Video Management Systems has four themes to deal with and they are

  • a.)    Digital Video Recorders (DVRs)- Digital Video Recorders are devices which have software, hardware and storage capacity embedded in them. They accept analog camera feeds and also support remote viewing of videos over IP. DVRs can be installed in a simple way and still they have their own set of demand among the professional buyers.
  • b.)    Hybrid DVRs- Hybrid DVRs support recording/viewing of video feeds obtained from analog and IP cameras. Although, their main purpose is to support analog camera feeds, they can also serve IP camera feeds, if in case, the surveillance environment is filled with a mix-up of analog and IP cameras.
  • c.)    NVRs- Network Video Recorders accept video feeds from network cameras and in order to record videos from analog cameras, an encoder has to be used.
  • d.)   VMS- Video Management Software does not come with any hardware or storage attached to it and is in no way similar to a DVR/NVR. In order to obtain more freedom to manage the video feeds, video management software must be loaded onto a server. It gives the configuration ability to the administrator and offers a great set of control on managing the surveillance cameras.

4.) Video Storage- Mainly, surveillance videos are stored in order to retrieve and review them for future needs. The average storage duration is 30 days and is practiced globally. Depending on factors such as cost of storage and the value the stored video offers, the duration of the video storage is determined. Video Surveillance demands huge amount of storage and can reach up to 100s of TB in some cases. While going for the selection of surveillance storage, there are four options which are available.

  •  a.) Internal Storage- DVRs and NVRs are built with internal storage which varies from vendor to vendor.
  • b.) Direct Attached Storage- When the storage media are located out of the DVR’s or NVRs or servers then they are called as Direct Attached Storage (DAS). They are connected and accessible through USB ports. An external hard drive is a good example of a DAS.
  • c.) Network Storages such as NAS, SAN or IP SAN act as storage pools, accessible via IP network.
  • d.) Onboard Camera Storage- Nowadays, surveillance cameras are being offered with onboard SD card support. So, cameras can record locally on-board, thus reducing network use and dependency.

5.) Video Recording- Recording a surveillance video to the video storage depends on factors such as recording resolution of the camera; whether it is done based on motion detection or on continuous basis and at what frame rate do the videos have to be recorded. Recording based on resolution and frame rates can influence the need for higher storage capacity of video storage to a large extent. Continuous recording will usually waste storage space and motion based recording has its own tradeoffs.

6.) Video Analytics- With the help of video analytics technology, scanning and analyzing of video feeds is possible. So, this action facilitates identification of threat or any kind of unfortunate event. Additionally, Video Analytics deployment on a Video Management System (VMS) also enables the intelligence of storing the videos based on the presence or absence of the motion.

7.) Viewing of captured video feeds- This can be done through local viewing, where video feeds are viewed from DVRs, NVRs or servers directly. Remote PC viewing is also effective as viewing of live and recorded videos through web applications is possible. Nowadays, mobile viewing through tablets, iPads and androids has become a technological fad. When hundreds and thousands of cameras are available in a surveillance environment, video wall viewing becomes practical. In this format, large screens are placed and a group of people keep an eye on the activities shown on the screen to respond to any urgent need of visual intelligence or video feeds.

8.)Integrating videos with other systems- Integration of video surveillance with other security operations is commonly seen in large organizations. Access control integration with video surveillance system is a common practice. However, budget plays a criterion in turning these options into reality.

Hope this serves as a basic guideline to beginners in IP surveillance field and gives them an overview of all the fundamental aspects of designing and deployment of an IP video surveillance system.

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StoneFly™ StoneFusion integrates with Permabit Albireo Deduplication technology

StoneFly, Inc, the pioneer of iSCSI storage is proud to announce that its StoneFusion Network Storage Operating System architecture will support data deduplication by integrating with Permabit Albireo Data Deduplication Software in order to further enhance storage optimization in enterprise environments.

StoneFly™ has been delivering block level storage intelligence in its IP SAN solutions with the help of its award winning and patented StoneFusion software. Benefits like increase in storage utilization through resource consolidation, storage provisioning, centralized access control, volume management were being offered in iSCSI SAN solutions of StoneFly till date.

Additionally, advanced storage services like mirroring, replication, encryption, snapshots, thin provisioning and active/active clustering were also being offered in StoneFly™ SAN appliances, possible due to StoneFusion Operating system.

Now, by partnering with Permabit, StoneFly will be able to add data deduplication ability to its solution and that too without the decline in performance and differentiating capabilities.

“We are committed to work with technology partners in order to deliver the best solutions to meet our customers’ storage needs,” said Mo Tahmasebi, CEO & President of StoneFly, Inc. He added, by Implementing Permabit Albireo into our StoneFly solutions we will provide widest range of options through additional storage optimization feature that offer a cascading amounts of benefits through the IT infrastructure.

“Deduplication is greatly sought after feature by companies which are in a look out for dependable and cost-effective management for their business critical data,” said Tom Cook, CEO, Permabit.  He added, StoneFly StoneFusion Network Storage Platform will be a perfect example of how original equipment manufacturers gain competitive advantage and leverage of Albireo’s data optimization technology in their existing as well as upcoming product line.

To more details please call 510-265-1616×271 or contact or


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StoneFly™ offers world’s first Scale Out 16/80G Unified NAS+iSCSI+ FC Storage

StoneFly, Inc. which has been persistently updating its product line with most modern technology has come up with world’s first Scale Out 16/80G Unified NAS+iSCSI+ FC storage solution based on its 10/40/80G Unified Storage concept. The company which is a subsidiary of Dynamic Network Factory has built 16/80G Unified NAS+iSCSI+ FC storage on its popular and award winning StoneFly Unified iSCSI and NAS Platform.

For all those enterprises which are in the look out for a product which can consolidate and optimize their storage needs, StoneFly USO 16 seems to be the perfect choice. California based StoneFly is offering its USO 16 with a dual 16G FC interconnects and 1/10/40/80G iSCSI + NAS solution at reasonable price.

As the demand for high-end storage capable of delivering higher throughputs and bandwidth is increasing; storage vendors are beginning to tackle this issue. Going with the trend, StoneFly has come up with USO 16 which happens to be world’s first Scale Out 16/80G Unified NAS+iSCSI+ FC storage.

“Organizations are in a look out to optimize their operations and bring down their CAPEX and OPEX costs. Keeping this in mind, StoneFly USO 16 is being offered as a unified, modular and high performance storage system supporting Fibre Channel Infrastructure” , said John Harris, Senior Director Product Planning. He added that USO 16 can be termed as the world’s first appliance with unified scale out16G Fibre 10/40/80G iSCSI and NAS storage solution, which has the speed, power and proven efficiency. This 64-bit-multi-core platform will deliver utmost performance to companies at competitive price point.

Technically speaking, StoneFly 16 appliance is designed to deliver 2-8 times higher performance than what an 8GB FC solution delivers. It is offered with 24 cores storage processor and dual active-active RAID controller at each node. To serve high end server environments like SQL server, a dual option of second level snapshot is presented in this appliance. Furthermore, StoneFly’s “Lego” approach modularity eliminates the need of a forklift upgrade in future.

Furthermore, StoneFly 16 storage solution is delivered as per the IOPS needs of the organization. Depending upon the application need this appliance will be made available with SATA, SAS and SSD drives.

StoneFly™ is readily available through commercial resellers and distributors. For more details, please logon to

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DNF Security launches affordable and lightning fast Falcon 80tiz NVR

DNF Security which has been launching innovative surveillance related storage solutions from time to time has come up with Falcon 80tiz NVR. This newly launched NVR platform will be a replacement to NVR Falcon 80tbz which is a popular hybrid video management solution in the company’s product catalog.

This affordable and lightning fast Falcon 80tiz NVR will be an ideal solution for organizations that have a mix-up of analog and IP camera solutions on premises.

Falcon 80tiz video storage is offered with advanced video management software, scalable performance and simultaneously incorporates storage capabilities ranging from 1TB to 24TB. The storage capability is offered with RAID 0,1, 5,6,10 technology and so data redundancy can be expected, depending on the raid levels which are selected.

What’s more? DNF Security Falcon 80tiz NVR + storage is available in space saving tower and 4U rackmount chassis and that too with the flexibility of having hot swappable drives and trays. So, if anything goes wrong with the hard drives, just that drive can be replaced without exposing the NVR to downtime.

For those, who are facing issues like inadequate bandwidth, DNF Security Falcon 80tiz offers a perfect solution. This Network Video Recorder with storage capability is loaded with a PCI Express 3.0 solution. This express switch is capable of delivering bandwidth ranging in between 500MB/sec to 1GB/sec and this is enough to ensure that network bandwidth gets eliminated.

DNF Security Falcon 80tiz attributes don’t end over here as it is ONVIF compliant and is compatible to work with all leading IP and analog cameras and Video Management Softwares. Moreover, the user is presented with the flexibility of choice to select either SAS/SATA hard drives which depends upon their application needs.

For more details, call (510) 265-1122 or visit DNF Security

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What is a Storage Controller?

Storage controllers have some sort of processors embedded to perform wide range of functions related to a storage system. A storage controller can be called as a storage computer which has the capability to operate as a single controller, in a redundant pair (dual controller) or as a node within a cluster of servers in a scale out storage.

Each storage controller has an Input/Output path to communicate to the storage network or to Direct Attached Storage. A processor that will handle the I/O movement of data and related functions such as RAID and volume management is also present in this controller.

Speed and Capabilities of storage controllers can show their direct impact in a modern data center environment.  So the first priority is to have a high speed storage infrastructure in order to process and perform functions involving data movement. The second priority of the controller is to efficiently communicate with the disk drives attached to a storage system. Thus, the performance of the controller is directly proportional to the number of drives.

With the presence of Solid-State drives a very small number of drives can generate more I/O than the Storage controller can support. Earlier, controllers used to have time to spend in between drive I/Os in order to perform certain functions. But with the presence of Solid-State Drives, latency issue has almost disappeared.

A controller’s performance capabilities also turn crucial as the processor in it will be responsible for complex functions such as snapshots, cloning, thin provisioning and replication.

Thin provisioning, Snapshots and clones can become burdening, since they allocate storage space on a dynamic note. So, high processing capabilities such as connecting to the host for capacity pre-allocation and then working in the background to fulfill those storage commitments becomes essential.

Automated tiering where data is moved in between different storage classes also needs high performance capability driven storage controllers. In this environment the controllers need to analyze access patterns and statistics of different applications in order to move data.

So, in coming days, the importance of a storage controller will increase with the influx of more outstanding developments in techniques like De-duplication.

From the user perspective, importance should be given to the capabilities of a storage controller. You need to carefully access and judge the future needs of your storage and then go for the selection of the controller based on its performance capabilities. If a feature such as addition of CPU intensive features is available, then it will be an added advantage.

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Understanding Scale-Up and Scale-Out Storage

A scalable storage is a data storage system which allows the users to grow their storage resources in line with their business requirements. It addresses the challenges created by legacy systems which present storage limitations.

Scalable storage systems are two types 1.) Scale-up storage system 2.) Scale-out storage system. In scalable storage architecture the functionality and performance are maintained on par with the storage resources expansion. It’s a great advantage for the IT managers who are challenged with the infrastructural growth issues, as they can manage the growth of their data within limitation of the IT budget without having to do a costly “forklift” upgrade.

Difference between Scale-up and Scale-out storage

Many IT managers are in confusion that Scale-up Storage and Scale-out storage are synonymous. But in reality they are two different concepts related to storage expansion

  1. Scale-Up Storage- Scale-up means taking an existing storage system and adding capacity to it in order to meet the capacity demands. That is adding up storage capacity in the same node and thus making the node bigger. The point to be noted over here is that a scale-up storage also requires additional space, power and cooling requirements, but without the need of an additional controller.
  1. Scale-out Storage- In this architecture, additional storage called nodes are added horizontally to increase capacity and performance. The only difference in between a scale-out system and adding of additional hardware onto the floor space is that Scale-out is still considered as a single system. In a scale-out system additional power, cooling and space requirements have to be achieved along with the addition of controller functions.

Some systems come up with a combination of scale-up and scale-out.

Generally, start-ups commence with simple storage, but it turns complex when there is data growth and need to upgrade arises. Securing additional capacity will be cited as the most common reason to upgrade a storage system in order to accommodate more users, files, applications and attached servers.

In addition to capacity, the other storage resources which have to be available with the growing demands of an organization are computing power and bandwidth. It is evident that in the absence of enough Input/Output bandwidth, the users will face difficulty in connecting to the servers due to network bottlenecks and thus the overall performance of the entire storage system will be in jeopardy. Coming to computing resources, the need for additional services like snapshots, replication and volume management generates the need for highly qualified storage software.

The disadvantage with legacy scale-up systems is that capacity is added as per requirement, but bandwidth and computing power remains as it is. So, as a result the performance will be high on the very first day of use. But gradually the performance starts to degrade, which prompts the need to overbuy storage compute power and bandwidth, thus it increases the costs.

In scale-up storage, after it reaches the performance peak the compute and bandwidth capabilities of the storage engine have to be replaced or additional stand-alone storage system has to be purchased. The first option of forklift upgrade will surely be expensive; while the second option becomes a management nightmare as additional IT staff has to be hired.

In scale-out storage architecture, there are individual storage components called ‘nodes’. Each node is enclosed with capacity, processing power and storage I/O bandwidth. As the addition of nodes takes place the three resources in the system will also be upgraded simultaneously. Additionally, the nodes are interconnected by a high speed network and so they can communicate with each other. So no matter how much capacity is added in a scale-up architecture, the performance of the system will be increasingly faster. In a scale-up storage system, granular expansion of various storage resources can be achieved. So purchase of only the resources which are needed is possible.

Scale-out storage software plays an important note in making the interconnected nodes accessible as a single storage system to the servers and storage administrators. So, the nodes are made into a single cluster or grid and the storage cluster software administers the writing of data across all the nodes in the scale-out storage infrastructure. So, the data writes and data reads are spread across more processors and I/O connections in the clusters. It is also essential that any node in the scale-up architecture must act as a control node at any time.  If in case, the data path has to be routed through a single control node then the cluster storage system will revert to something which has the same limitations.

At the same time, storage cluster software should also be capable to take benefit of the extra RAM that each node carries to the cluster and must be able to leverage it to promote enhanced performance. Another key function of the storage software is the ability to support wide range of workloads types with the use of additional storage compute and I/O resources. Finally, the storage software must support all the data services that IT executives are expecting from a storage system like snapshots, thin provisioning, cloning, replication and automated storage tiering.

Modern data centers use scale-out storage

Modern data center architectures are ideal environments for scale-out storage as there is a mixture of workloads and I/O demands. Since, user files are large in size and numerous in numbers, frequent sequential processing becomes essential. For this reason, data centers are moving towards server virtualization in order to cut down on hardware costs and IT staff.

In order to deal with the function of sequential processing of larger and numerous files, Scale-out storage is uniquely positioned to address this need. As bandwidth and computing resources grow simultaneously with the capacity, the need to fine-tune the system for exceptional cases gets reduced in this architecture. Hence, with the default system configuration, sufficient amount of performance can be achieved and that too without the need for expertise storage managers.

Although scale-up storage systems vendors prop up that their concept will support management interfaces, capabilities and cross-system file systems; these three factors are not satisfied in reality. For instance, if an IT manager needs to add a server to the scale-up storage setting, then he needs to first evaluate and determine which resource is the best candidate to support that server’s workload.

In a scale-out storage system, everything seems like a single system and one volume. So, the IT manager simply needs to connect the server to the storage and start using it. In case the new server work functions spike up the need for more storage, then a new node can be added and it brings in more bandwidth, computing resources into the environment.

So, scale-out storage can be an ideal solution for modern data center where workload and high performance needs cannot be compromised while trying to bring down the management costs.

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How long a Surveillance Video should be stored?

Choosing a video storage solution for a surveillance environment can be a difficult task in reality. If we happen to zero upon a solution, the next question will be how long the captured surveillance videos have to be stored. Is it for 1 week, 1 month or 1 year? This has become a fundamental question to every surveillance system manager. As the duration period of video storage becomes critical, when a situation to produce video evidence arises. If the surveillance video is stored for too short time, then it can make you helpless in situations when a piece of recorded evidence is required. If it is done for too long time it could waste the fair amount of IT resources and budget in most cases.

So, here is an analysis which will help in examining how long a surveillance video has to be stored in a surveillance environment.

Storage fundamentals followed while designing a surveillance system depend on the frame rate and resolution of the recording cameras: how much storage will be needed (approximately)? What is the storage type which has to be selected (NAS/SAN)? Which features should be covered by the storage appliance, say redundancy, RAID usage, some other? Last, but not the least will be to determine whether the recording of videos will be in continuous mode or on motion based. It is a wise decision to go for intelligent way of motion based recording as it will save a lot of storage space from being wasted and thus will help in saving IT resources.

The key drivers which influence the storage duration factor are cost of maintaining the storage and how long does it take for the users to know that the need for video evidence from the surveillance system is needed as well as how long does it take to retrieve the video.

Incidentally, demand for video evidence is usually within a period of few days or weeks and some extra time is needed to retrieve the video from the sources.

To be honest on the above aspect, there are no international or national standards to be followed while designing surveillance storage. All depends on the needs of the surveillance environments and budget allotted for that particular IT activity. But generally, 30 days to 90 days period of surveillance recording is generally followed in this regard. This includes European continent as well, where a standard of 30 days minimum/maximum is followed. But this can be altered as per the requirements of the surveillance needs of an organization/enterprise.

To be specific, they are only four themes which emerged as applications requiring long term storage duration.

Government organizations related surveillance storage must be maintained for 90 days and that has become a mandatory in all parts of the world. But, certain FDA compliance laws suggest having a 180 day (6 months) surveillance storage period. Due to the recent terrorist activities and increase in security concerns, it has become unofficially mandatory in United States, Australia and United Kingdom to maintain surveillance videos related public places for longer periods such as 6 months.

Till April 2013, due to privacy concerns the monitoring videos were only maintained for a period of 30 days and that too with many stipulated rules in place.

But in wake of events like the unfortunate incident in Boston on April 2013, many government/private organizations have started revising the minimum requirement of the video storage retention to longer periods of time.

Storing surveillance videos from interview and interrogation rooms for longer duration is seen in police departments. The videos are retained for a period of 999 days in general. In a military detention center, the videos are retained for up to 7 years.

All financial institutions including Banks & ATMs will need a 180 day surveillance video storage. For organizations that face significant litigation risk such as food or chemical firms will go for a 6 month -5 years period of video surveillance storage.

Going by the technological trend, megapixel driven surveillance can also show its influence on video storage needs. In order to get a higher clarity in images, megapixel IP cameras are deployed in surveillance activities. The higher the MP resolution will be, the more size the captured image will occupy on the video storage. For this reason, megapixel camera surveillance system demand significantly shorter time to keep surveillance videos. However, all depends on the needs of the application environment and the value the stored videos generate.

Impact of project size on storage duration can also be seen in environments, as integrators involving in larger projects insist on keeping videos for longer time than the small project specialists.

Hence the conclusion is that there isn’t any general hard and fast rule as to how long you should keep your video storage intact. It completely depends on the application needs and compliance requirements.

Note: The above said time periods were described from the experience of the integrators who had more than a decade long experience in the surveillance field. The duration might vary and there is no need to follow the specified periods as a mandatory.

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What is SAN Zoning?

While discussing about SAN topologies and switches, many of you might have come across the term ‘SAN Zoning’. This particular term turns critical when a Storage Area Network layout is filled with more than a couple of dozen devices. In early days of its existence, SAN Zoning did not get its due share of importance, as many cited that it was not a Fibre Channel SAN Standard. But now it is very much an evolving area in standards and implementation. In order to know more about this technical term, let us take a closer look at it.

SAN Zoning

It is a fact that unlike a NAS, SAN restricts its user access to a specific storage application space. That is, like in a Network Attached Storage, SAN users cannot access every file on the centralized storage. It restricts the file access of users intended for a specific application. So, here comes Zoning, whose primary function is to control who can see what in the SAN. In every server, there are various mechanisms where server applications are allowed to see and talk to other devices.

At the low level, an HBA’s firmware and/or driver can have the control of masking the server from other devices. Additionally, the Operating System will have the configuration ability to control the devices it tries to mount as a storage volume. So, extra-layered software is used by many IT people for volume management, clustering and file system sharing, which will also help in controlling application access.

In case of Storage Zoning, if we can ignore RAID subsystems and JBOD, then there is a form of selective presentation on most disk arrays. The array is configured in such a way that the list of servers accessing LUNs and their service requests and denials can be traced out. In switch zooming, most of the FC switches support zoning in order to control devices and their access to ports.

Functioning of San Zoning

In order to understand functioning of SAN Zoning, let us get into it in a technically precise way. As soon as a node connects with a fabric, it does a fabric logon. By doing so, the device gets a 24-bit address allocation useful for routing in the fabric. The device has a World Wide Name programmed in its hardware as per its unique port. The node WWN also identifies the node or device and will show up the same on each port.

As soon as a device logs on to the name server services in SAN environment, it registers itself. This allows the SAN to build up database of all the devices in the fabric, with the use of mapping of node and port WWN. This will also include the FCP device which talks with SCSI Commands over Fibre Channel.

This makes the server to ask the name server the list of the FCP devices seen on the fabric and this is how zoning comes into affect. The name server responds with the list of FCP devices which are in the same zone, i.e. it traces out only those devices which it is supposed to know.

As a result the list of all the 24-bit addresses will be available with the server, which in-turn does a logon to each one and finds out what the device is all about (FCP/SCSI) and thus constitutes to Zoning.

What type of SAN Zoning should be used?

Going with little of each of the following approaches may prove beneficial

  • By utilizing the capability of operating system or software for controlling of devices/LUNS mounted on the server.
  • Using Zoning on fabric and selective presentation on storage array, isolation of a PC using network analogy to hack the files in the corporate system is possible. For preventing such incidents, having an access control list on files in the file system will be advantageous.
  • In addition to it, firewalls, security gateways and packet filtering will also be helpful in protecting the data.
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Pros and Cons of Edge based video Recording

Edged based video recording is now the latest craze in IP Video Surveillance field, as it eliminates the troubles associated with network bottlenecks involved in centralized video recording systems. This article will shed some light on how the system of edge based recording works and what are the pros and cons associated with it.

How a Conventional Security Surveillance Design Works

In an IP surveillance environment, video recording takes place at Network Video Recorder (NVR) or centralized recording server. The video feed from the IP camera is pulled down by the server in a consistent manner and then it records the video onto the storage media. Usually, in order to utilize the storage resource to maximum, IP cameras are set to motion detection alert, where the videos are captured, only when a motion is detected and then the image is transferred to the storage. During this process, the server continuously streams the video feeds in search of any motion detection. As soon as the motion is detected, the video is captured and recorded.

The whole process is similar to that of an analog surveillance system; except for the fact that the whole process is carried out in more intellectual way in network video system.

Disadvantages of Centralized Recording System

In a network video approach the following problems are observed.

Bandwidth- A centralized network video approach is termed as a foe to network bandwidth. In a centralized camera approach, the stream is consistently pulled by the network cameras, regardless of recordings being carried out. The problem deteriorates when the network gets completely saturated.

Server Specification- Needless to say, a centralized server must be well capable to analyze the footage from the number of cameras. As the camera count increases, more bandwidth is required and more processing of video streams should be carried out. When all the network cameras start to communicate with the server at a time, there is a high probability of network bottleneck creation on low cost hardware, which reduces the effectiveness of the system.

Fault tolerance- When the camera control is being monitored by a centralized server, in the case the server goes down for some reason, video recording will not take place from there on. If in case the server gets damaged, there is a possibility of recordings getting lost. Although, this situation can be tackled with a failover server, additional costs on hardware and software will be cumbersome.

Here comes Edge Recording

Edge recording feature in an IP camera allows the recording functionality take place on the camera itself. IP cameras are now coming with edge based recording feature, where flash memory based SD/MicroSD memory cards are deployed on the network camera itself. The captured video can be later-on transferred to network storage or to a central server.

Edge recording benefits

As the recording takes place at camera level, there is no impact on network.

Since, motion detection feature is entertained at IP camera level, no footage is sent until motion is detected. As soon as the motion is detected, the network camera records the footage and will stop as the motion ends.

Ever since, the intelligence of processing and recording functionality is at camera level, the need for highly sophisticated storage drives has come down.

With in-built storage capacities of network cameras increasing from day to day, the need for recording server is getting less prominent. As soon as the camera loses network connectivity, it stores the captured footage to its on-board storage media and transfers it to the server when the connectivity gets restored.

Edge based recording disadvantages

As the surveillance storage is distributed on the network, managing the multiple storage locations becomes difficult. However, nowadays IP camera manufactures are coming up with intelligent monitoring feature of on-board storage, where footage monitoring throughout the network is made possible.

As the processing power of each camera is high, the cost of the device will be more than a normal IP surveillance camera.

ONVIF compliance is also hard to achieve as devices with this processing ability might not support devices from different manufactures for video exchange. If this feature is still achievable, then again the device may become too expensive.

Coming up with the best of both worlds

IP cameras are now being manufactured with the feature of Edge and centralized storage system. As mentioned in earlier paragraphs, whenever a network downtime occurs, the cameras record the footage to the camera and when the network is back, the footage is sent back to the centralized server. This approach will improve reliability as data loss will be nil, but still needs a centralized server causing data bottlenecks and increase of cost.


It seems like both sides of the argument are valid, as the advantage is that it reduces bandwidth demand and offers fault tolerance. At the same time, it eases management and also lower per-camera costs of centralized recording.

However, additional costs of both camera and storage devices, coupled with lack of support to ONVIF design structure may make Edge based recording an upcoming prospect of IP Video Surveillance. It is also a fact in reality that manufacturers of network cameras have already begun to focus on the Edge based surveillance and are coming up with varied, as well as improved products in coming days.

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Advantages of using a Storage Area Network

Storage Area Network (SAN) happens to be a cool solution for many enterprise IT storage needs, as it helps in consolidating all the business data into one single storage appliance. A SAN solution is a collection of storage disk drives which run on a LAN or a WAN network. The best part of SAN is that in the event of one disk failure, with the help of RAID technology, this storage system will be able to rebuild data from the faulty disk onto a spare disk. That also gives brings the question that what makes a SAN solution so efficient in the data storage domain? Well, here is an answer to that and also an overview on how SAN always has a value worth its cost.

Reasons to use SAN

Better disk utilization- Better disk utilization is the primary benefit of using SAN storage. When your storage is available in a centralized manner then everything can be managed as a single entity. This gives you an advantage to slice up the different pools of storage resources at a network level and assign the storage in an intellectual manner to the available server applications. If you missed a SAN deployment then you would have been practicing the tradition of purchasing tons of disks and sticking them to an expensive server. In this practice, high cost investment is needed and disk space also gets wasted as most of your enterprise applications may not need the available space at all times.

SAN for disaster recovery for multiple applications- If your data center/ IT environment has critical servers running on applications which cannot be let down, then there needs to be a data continuity solution in place, which can act as a failover when a disaster strikes. If this indeed is the scenario then SAN based DR solution will be the right choice. Since the volume of downtime is critical in most organizations when disaster strikes, a SAN solution will effectively reduce the downtime number to a negligible value.

For improving the availability of the application-  In order to serve those applications which need high availability, a SAN solution will be the right storage medium. There are cases where applications fail due to silent data corruptions or due to some hardware/software fault. But in a storage array of a SAN, data protection algorithms are set to the peak, to ensure data consistency.

SAN can reduce backup time- If an enterprise or a data storage environment is facing a situation where its backup is taking too long, then SAN solution needs to be deployed in these circumstances. The technology of a SAN solution is such that it can make a duplicate of a data copy within no time. Thus these duplicates can serve as a backup for your data or act as a source to backup the data to tape library.

Reasons when not to use a SAN

While this analysis is related to the advantages of SAN but in order to make it complete and “fair”, let us also go over reasons for not using a SAN as well. From technical point of view, there isn’t any drawback. However, a SAN will not make sense, when the right staff, budget and application requirements are not present to support it.

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