for Network Video RecorderSeagate Technology ... Hard drives in a CCTV digital recorder or NVR continually write to themselves 24/7. The average hard drive you buy from a retail store

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for Network Video Recorder

Table of Contents

Introduction ................................................................................................................... 3

Favorite HDD for Surveillance ..................................................................................... 3

Western Digital .............................................................................................................. 4

Seagate Technology ................................................................................................... 4

WD HDD .......................................................................................................................... 5

Xe......................................................................................................................... 5

Re ......................................................................................................................... 8

Se ....................................................................................................................... 10

Purple ................................................................................................................ 12

WD HDD Comparison ................................................................................................. 15

Seagate ....................................................................................................................... 16

Surveillance HDD ............................................................................................. 16

Seagate Video 3.5 HDD ................................................................................. 17

Seagate HDD Comparison ....................................................................................... 18

HDD Capacity Selector ............................................................................................. 20

Some Practical Notes ................................................................................................ 21

Figure 1. Xe Decision Criteria ............................................................................................. 5

Figure 2. Re Decision Criteria ............................................................................................. 8

Figure 3. Se Decision Criteria ........................................................................................... 11

Table 1 WD Xe Specs ........................................................................................................... 7

Table 2. WD Re Specs ........................................................................................................ 10

Table 3. WD Se Specs ........................................................................................................ 12

Table 4. WD Purple Specs ................................................................................................. 14

Table 5. WD Series Comparison ...................................................................................... 15

Table 6. Seagate Surveillance Series Comparison .................................................... 18

Table 7. Industry's Most Suitable Surveillance HDD ................................................... 19

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Introduction

Favorite HDD for Surveillance

Hard drives are essential for digital security and surveillance Network Video Recorder (NVR)

systems that perform around the clock monitoring and event archiving. It is very important to

know what hard disk storage is reliable to use in NVR systems. When it comes to digital video

recorders, network video recorders or custom built servers for video surveillance recording,

your choice of hard drives can make or break you. In past years many DVR manufacturers

out there, had experienced hard drive failures in short term, which put a black eye on the

manufacturer’s reputation. In addition, redundancy in a storage system allows video, or any

other data, to be saved simultaneously in more than one location of the storage system. This

provides a backup for recovering video if a portion of the storage system becomes

unreadable.

Hard drives in a CCTV digital recorder or NVR continually write to themselves 24/7. The

average hard drive you buy from a retail store is not made for video surveillance recording

duty. So later in the following sections, we review some of the most suitable HDDs for the

required purpose to affect your decision on how to choose an appropriate HDD and its

corresponding appliances.

Hard drive failure is perhaps the number one cause of lost video in a surveillance system. But

which hard drive manufacturer is the most reliable? Are all hard drives the same?

Recently a survey is conducted among 100 integrators about their preferred hard drive for

surveillance. Visit: http://ipvm.com/updates/1278

Among those with a preference, more integrators chose Western Digital, at 27%, than any

other. Seagate was second, at 23%. Hitachi was a distant third, with 6%. A few other

manufacturers received a mention, though none managed to gather more than 1%.

Seagate and Western Digital both issued press releases announcing new 1 up to 4TB drives

optimized for Video surveillance.

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Western Digital

Seagate Technology

In Feb, 2014 WD announced the availability of WD Purple a purpose-built line of 3.5-inch,

high-capacity hard drives for surveillance applications, Designed specifically for video

surveillance units, WD Purple hard drives excel in new and existing home and small business

security environments with up to eight hard drives and up to 32 high-definition (HD) video

cameras. WD Purple hard drives are available in capacities from 1 TB up to 4 TB. In addition,

WD Purple drives support up to eight drives and 32 HD cameras so there is the flexibility to

expand for future system coverage.

Optimized to withstand the demands of always-on digital PVR, DVR and NVR recording

environments, WD Purple hard drives offer low power consumption and many advanced

performance features typically reserved for enterprise-level storage.

Seagate, also introduced its seventh-generation hard drive disk (HDD) engineered

specifically for surveillance and video analytics applications— the Seagate® Surveillance

HDD. The Surveillance HDD is a world-class HDD purpose-built for storing and accessing video

analytics, improving data integrity and keeping systems in the field longer.

A 3.5-inch drive, the Surveillance HDD is available in capacities up to 4TB and can store up to

480 hours of high-definition (HD) content making it one of the highest-capacity drive

designed specifically for surveillance applications. Designed to scale video storage, the drive

now incorporates rotational vibration (RV) sensors enabling it to reliably perform in systems

with up to 16 drives, making it ideal for small-to-medium businesses such as casinos or

manufacturing plants where bulk storage for HD video and video analytics are highly valued.

Designed to support surveillance recordings from a number of cameras no matter their

resolution requirements, Surveillance HDD supports up to 32 channels and easily handles the

higher write workloads required by surveillance systems. It also supports the flexibility required

to scale a surveillance solution, supporting more data for longer periods of time and meeting

industry archive and resolution requirements. These features, coupled with the integrated R/V

sensors, improve drive performance in multi-drive and RAID systems and increase the value

of surveillance data by delivering the highest data integrity possible.

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WD HDD

1. HDD Xe Performance (High Density Performance Storage for Demanding Application)

WD has focused significant engineering effort for the Xe line. The drives incorporate a

bevy of technology designed to ensure long term operation in the enterprise. This feature

set is highlighted by key items like Rotary Acceleration Feed Forward (RAFFTM), which

optimizes operation in vibration-prone environments, and NoTouch ramp load

technology, which means the head never, touches the disk media. These features and

others lead the Xe to an industry-high 2,000,000 hours MTBF. In the following section we

will briefly drill down to its main features and details:

a. Main Features

Figure 1. Xe Decision Criteria

i. Ultra-Fast SAS Storag. WD Xe delivers 6 Gb/s transfer rates, plus

sequential data rate of 204 MB/s.

ii. Designed for quality and reliability. Datacenter drives undergo at least

5 million hours of functional testing, and over 20 million hours of

comprehensive Interoperability testing in an extensive array of server

and storage systems. Please see the product AVL list for more info.

iii. 3.5-inch performance adapter. WD Xe comes pre-mounted in a 3.5-

inch performance adapter, providing easy installation into legacy 3.5-

inch server and storage system slots, while optimizing the drive’s

thermal management efficiency. (HKHG models only)

iv. Dual processor. Twice the processing power to maximize performance.

v. Dual port, full duplex connectivity. A head positioning system with two

actuators that improves positional accuracy over the data track(s).

The primary actuator provides coarse displacement using

conventional electromagnetic actuator principles. The secondary

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actuator uses piezoelectric motion to fine tune the head positioning to

a higher degree of accuracy.

vi. StableTrac. The motor shaft is secured at both ends to reduce system-

induced vibration and stabilize platters for accurate tracking during

read and write operations.

vii. Multi-axis shock sensor. Automatically detects the subtlest shock

events and compensates to protect the data.

viii. Lower your power consumption. The 2.5-inch WD Xe SAS drive requires

less than 8 watts to operate. Its small form-factor allows for more

system airflow resulting in lower cooling costs. The 3.5-inch WD Xe SAS

drive delivers up to 67% lower power versus 3.5-inch 15,000 RPM drives,

which can result in substantially lower total cost of ownership (TCO)

while increasing capacity and reliability.

ix. Vibration Protection. Enhanced RAFF technology includes

sophisticated electronics to monitor the drive and correct both linear

and rotational vibration in real time. The result is a significant

performance improvement in high vibration environments over the

previous generation of drives.

x. RAID-specific, time-limited error recovery (TLER). Prevents drive fallout

caused by the extended hard drive error-recovery processes common

to desktop drives.

xi. Thermal extended burn-in test. Each drive is put through extended

burn-in testing with thermal cycling to ensure reliable operation.

xii. Dynamic fly height technology. Each read-write head’s fly height is

adjusted in real time for optimum reliability.

xiii. NoTouch ramp load technology. The recording head never touches

the disk media ensuring significantly less wear to the recording head

and media as well as better drive protection in transit.

xiv. Self-encrypting Drive (SED) Option. SAS Drive: Optional secure model

for encrypting drives – Utilizing an AES 256 bit encryption engine for

Crypto erase capability, WD supports the industry standard

implementations of both the SCSI Sanitize command with Crypto Erase

and the Trusted Computing Group (TCG) command set.

xv. The WD advantage. WD puts our datacenter products through

extensive Functional Integrity Testing (F.I.T) prior to any product launch.

This testing ensures our products consistently meet the high quality and

reliability standards of the WD brand. Following a FIT test the Enterprise

System Group (ESG) testing validates interoperability with HBAs,

operating systems and drivers to ensure an even greater level of

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quality, reliability and peace of mind. WD also has a detailed

Knowledge Base with helpful articles and software utilities. Our

customer support lines have longer operational hours to ensure you

get the help you need when you need it. Our toll-free customer

support lines are here to help or you can access our WD Support site

for additional details.

b. Specification

Table 1 represents the main physical specs of the device.

Table 1 WD Xe Specs

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2. HDD Re Durability (Durable Capacity Storage for High Availability Storage)

Western Digital RAID Edition (RE) 4TB Enterprise drive takes the RE family to the 4TB

capacity limit. The new drive offers a SATA 6Gbps interface with RAID-specific, time-

limited error recovery (TLER), dual actuator technology, enterprise build quality to name a

few of the features that make the Western Digital RE's ideal for Enterprise users looking for

the fine balance between performance and capacity. In the following section we will

briefly drill down to its main features and details:

a. Main Features

Figure 2. Re Decision Criteria

i. High capacity nearline drive. Massive capacities up to 4 TB suit even

the most demanding datacenter or cloud storage needs.





iii. Dual port processor. Twice the processing power to maximize

performance.

iv. Dual port, full duplex connectivity (SAS only). Offers higher reliability,

performance and data availability by eliminating single points of

failure, designed for high-availability mission-critical enterprise systems.

v. Dual actuator technology. A head positioning system with two





a higher degree of accuracy. (2 TB and above).

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vi. StableTrac. The motor shaft is secured at both ends to reduce system-


read and write operations. (2 TB and above)

vii. Multi-axis shock sensor. Automatically detects the subtlest shock


viii. Designed for heavy application workloads. Designed to handle up to

550 TB per year in any heavy application datacenter with the highest

workload capabilities of any WD 3.5 hard drive. Up to 6 Gb/s transfer

rates and sustained sequential data rates of up to 182 MB/s, deliver

performance and reliability to any datacenter environment.

ix. Vibration Protection. Enhanced RAFF technology includes

sophisticated electronics to monitor the drive and correct both linear

and rotational vibration in real time. The result is a significant

performance improvement in high vibration environments over the

previous generation of drives.



to desktop drives.

xi. Thermal extended burn-in test. Each drive is put through extended


xii. Dynamic fly height technology. Each read-write head’s fly height is


xiii. NoTouch ramp load technology. The recording head never touches



xiv. Self-encrypting Drive (SED) Option. SAS Drive: Optional secure model

for encrypting drives – Utilizing an AES 256 bit encryption engine for

Crypto erase capability, WD supports the industry standard

implementations of both the SCSI Sanitize command with Crypto Erase

and the Trusted Computing Group (TCG) command set.

xv. The WD advantage. WD puts our datacenter products through

extensive Functional Integrity Testing (F.I.T) prior to any product launch.

This testing ensures our products consistently meet the high quality and

reliability standards of the WD brand. Following a FIT test the Enterprise

System Group (ESG) testing validates interoperability with HBAs,

operating systems and drivers to ensure an even greater level of

quality, reliability and peace of mind.

WD also has a detailed Knowledge Base with helpful articles and

software utilities. Our customer support lines have longer operational

10

hours to ensure you get the help you need when you need it. Our toll-

free customer support lines are here to help or you can access our WD

Support site for additional details.

b. Specification


3. HDD Se Scalability (Optimal Storage for NAS and Scale-out Storage)

The WD Se HDD is the company's latest 3.5" enterprise-class hard drive that ranges in

capacities up to 4TB, spins at 7,200 RPM and interfaces over SATA 6 Gb/s. The WD Se is

designed to provide robust storage for large-scale NAS deployments, replicated

environments, bulk cloud storage, and backup and archiving. The WD Se isn't geared

toward revving up to the highest IOPS offered by an HDD; the drives are more affordable

than performance variations and offer features required for data security by SMBs and

the growing mid-range NAS market. That said, WD designed the Se series to still support

moderate-workload applications with maximum sustained transfer rates claimed at up to

171MB/s. In the following section we will briefly drill down to its main features and details:

Table 2. WD Re Specs

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a. Main Features

Figure 3. Se Decision Criteria

i. Cost effective enterprise-class storage. Get the right blend of

performance, reliability and capacity and keep your total cost of

ownership low.





iii. Dual port processor. Twice the processing power to maximize

performance.

iv. RAFF rotational vibration cancellation technology. Enhanced Rotary

Acceleration Feed Forward (RAFF) technology includes sophisticated

electronics to monitor the drive and correct both linear and rotational

vibration in real time. The result is a significant performance

improvement in high vibration environments over the previous

generation of drives.

v. Dual actuator technology. A head positioning system with two





a higher degree of accuracy.

vi. 24x7x365 reliability. Choose the storage foundation specifically

designed for SMB to high-end NAS and large-scale datacenter

replication environments running 24x7x365.

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vii. StableTrac. The motor shaft is secured at both ends to reduce system-


read and write operations. (2 TB and above)

viii. Multi-axis shock sensor. Automatically detects the subtlest shock


ix. NoTouch ramp load technology. The recording head never touches





to desktop drives.

xi. Maximum capacity for hyper scale environments. Build a massive data

footprint with capacities up to 4 TB - 144 TB per square foot.

xii. Thermal extended burn-in test. Each drive is put through extended


xiii. Dynamic fly height technology. Each read-write head’s fly height is


xiv. Ideal for. The Se is best suited for bulk cloud storage, replicated

environments, content delivery networks (CDNs), SMB network

attached storage (NAS), backup and archiving.

b. Specification


4. WD Purple

WD Purple Surveillance Storage offers exclusive AllFrame technology to bring you

premium reliability and peace-of-mind when installing your home or small to medium

business security system. WD Purple’s exclusive firmware upgrades work with ATA

streaming to reduce error pixilation and video interruptions that occur when desktop

hard drives are incorrectly used as storage in security systems. WD Purple Surveillance

Storage is built for 24/7, always-on, high-definition surveillance security systems that

use up to eight hard drives and up to 32 cameras.

Table 3. WD Se Specs

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a. Main Features

i. Engineered for compatibility. WD Purple surveillance hard drives are

built for compatibility with chipset manufacturers for seamless

integration into your new or existing video surveillance system. Check

out our compatibility selector to find out what surveillance drive is right

for you.

ii. Lower power consumption. Low power consumption is crucial in high-

temperature always-on surveillance environments. With exclusive

IntelliSeek technology, WD Purple drives calculate the optimum seek

speeds which lowers power consumption, noise and vibration that can

damage and cause desktop drives to wear out more quickly. When

you invest in a premium surveillance-class drive you worry less while

enjoying the benefits over a longer period of time.

iii. Optimized performance for up to 32 HD cameras. WD Purple hard

drives are optimized to support up to 32 high-definition surveillance

cameras, giving you the flexibility to upgrade and expand your

security system in the future.

iv. Ideal for. WD Purple storage is tested and recommended for use in

surveillance and security systems up to 8 bays and optimized for 32 HD

cameras. For additional surveillance capacity, look at WD datacenter

hard drives. WD Purple is not recommended for use in NAS

environments, please consider using WD Red hard drives for desktop

RAID and NAS environments or WD datacenter hard drives for

rackmount or large RAID configurations.

v. Key Benefits

- Reduces video frame loss with surveillance-class storage.

- Specifically tuned for surveillance security systems.

- Caching algorithms are tuned for write-intensive, low bit rate, high

stream count applications that are typical of surveillance applications.

- Priority change for write allocations and preemptive caching policies.

- TLER & ATA streaming support.

- Supports up to eight drives.

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b. Specification


Table 4. WD Purple Specs

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WD HDD Comparison

Table 5 shows a brief and at-one-glance comparison of the reviewed WD HDDs. Main criteria

for supporting the right decision upon appropriate HDD selection, may be RPM, Cache,

Processor, Vibration Protection, RAID, Heavy Workload Tolerance, 24/7 Availability, and

Security.

Table 5. WD Series Comparison

Type Xe Re Se Feature Quality and Reliability (Functional/Interoperability) /Million Hours

5/20 5/20 5/20

Form Factor 2.5 inch 3.5 inch 3.5 inch RPM 10,000 7,200 7,200 Interface SAS 6Gb/s SATA 6Gb/s SATA 6Gb/s Capacity 300~900GB 250GB~4TB 1TB~4TB Cache 32MB 32~64MB 64~128MB Dual processor YES YES YES Dual port, full duplex connectivity YES YES/SAS only N/A Dual actuator technology YES YES YES StableTrac YES YES YES Multi-axis shock sensor YES YES YES Low power consumption YES N/A N/A Vibration Protection (RAFF Technology) YES YES YES RAID-specific, time-limited error recovery YES YES YES Thermal extended burn-in test YES YES YES Dynamic fly height technology YES YES YES NoTouch ramp load technology YES YES YES

Environmentally responsible

RoHS Compliant and

Halogen Reduced

RoHS Compliant and

Halogen Reduced

N/A

Heavy application workloads N/A YES N/A 24x7x365 reliability N/A YES YES Self-encrypting Drive (SED) Option YES YES N/A

Ideal for

Enterprise Server and

Storage Application

Data Center and Cloud

Storage

Bulk Cloud Storage, NAS, Backup and

Archive

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Seagate

1. Seagate Surveillance HDD (Surveillance Drives Optimized for Reliability and Data

Protection)

The seventh-generation 4TB Seagate® Surveillance HDD (formerly SV35 Series™)

addresses the need for high-resolution cameras and camera counts, and ensures cost-

effective performance and durability in always-on surveillance systems. As drive

technology evolves, so do the applications that leverage them. With improvements in

motion sensing cameras, the Surveillance HDD now includes settings that can ensure

your drive is ready when your system needs to record.

4TB of storage capacity supports up to 16 drives and 32 cameras per system

Precision-tuned for surveillance workloads with high write work cycles

Reliably performs in multi-drive systems with RAID support

Rotational vibration sensors for reliable performance

Customize power settings to best support motion-activated cameras with Idle 3

support

a. Main Features

i. Build Better Video Surveillance Systems

The Surveillance HDD features storage power for the latest video

surveillance systems.

ii. Build scalable systems to support large streaming workloads with

support for ATA streaming and up to 32 cameras

iii. Surveillance-optimised firmware improves drive reliability up to 30%

and can reduce data loss

iv. Ready to work 24×7 supporting up to 400+ hours of high definition

content

1M hours MTBF

b. Consistent performance in multi-drive surveillance systems

The addition of RV sensors allows drives to reliably perform in systems with

up to 16 drives

The addition of RV sensors allows drives to reliably perform in systems with

up to 16 drives

Support for up to 32 cameras recording in high definition

c. Improve time-to-ready for motion sensing cameras

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d. Best fit application

i. NVR

ii. Embedded SDVR

iii. Hybrid SDVR

iv. Surveillance DVR

2. Seagate Video 3.5 HDD

Seagate® Video 3.5 HDDs deliver reliable 24×7 operation - optimized for low-power

consumption, quiet operation, smooth video streaming, high reliability and high

capacity.

i. Delivers up to 16 simultaneous streams of HD content

ii. 4TB video storage solution - up to 480 hours of HD video

iii. Quiet operation to enhance viewing and listening experience

iv. 24×7 operation for always-on demands DVR devices

v. Entry level or home surveillance system storage solution

a. 4TB = Up to 480 Hours of HD Content. Video 3.5 HDDs meet the growing

demand for more storage in DVR and media center applications with support

for up to 16 HD streams. Capturing, storing and viewing up to 480 hours of

video content are supported by the device.

b. Reliable DVR Storage. Media technology demands both reliability and energy

efficiency. Seagate Video 3.5 HDDs deliver some of the industry’s lowest

overall power consumption profiles, coolest operating temperatures and best

AFRs. Low-power profiles help DVR manufacturers achieve reduced overall

power requirements and support Energy Star compliance.

c. High Performance, Low Power Consumption. Video 3.5 HDDs meet the rising

demand for energy-conserving consumer electronics without compromising

performance. Seagate is committed to environmental stewardship that goes

beyond reduced power consumption. By design, the Video 3.5 HDD:

i. Contains up to 50% recycled materials

ii. Uses materials that are 70% recyclable

iii. Meets all RoHS and new REACH standards

iv. Is low halogen use

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Seagate HDD Comparison

Table 6 shows a brief comparison of the five surveillance type of hard drives by Seagate from Interface, Cache, RPM, Vibration Sensor, Camera number support, and so on.

Table 6. Seagate Surveillance Series Comparison

Type Surveillance SV35 Video 3.5 Feature Capacity 4/3 TB 3/2/1 TB 4/3 TB Interface SATA 6 Gb/s SATA 6 Gb/s SATA 6 Gb/s Cache 64 64 64 RPM 5900 7200 5900 Rotational Vibration Sensor YES NO NO Drive Bays Supported 1 to 16 1 to 6 N/A Cameras Supported Up to 32 Up to 32 Up to 16 Seek Average Read (ms) <8.5 <8.5 <12 Seek Average Write (ms) <9.5 <9.5 <12

Later in the following table, a brief comparison is made among reviewed HDD from WD and Seagate.

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Table 7. Industry's Most Suitable Surveillance HDD

Seagate

DV

R D

rive

Vid

eo 3

.5

3~4

TB

SATA

6 Gb/s

3.5 inch

5,900

64

24/7

NO

Up to 16

N/A

RoHS Compliant

and Halogen‐

Red

uced

Less than

SV35

None

None

DVR

SV35

3/

2/1

TB

1~3

TB

SATA

6 Gb/s

3.5 inch

7,200

64

24/7

NO

Up to 32

Up to 6

RoHS Compliant

1,000,000

None

Thermal M

onitoring En

abled

NVR Surveillance

Surv

eilla

nce

4/3

TB

3 ~ 4TB

SATA

6 Gb/s

3.5 inch

5,900

64

24/7

Rotational

Vibration

Sensor

Up to 32

Up to 16

Western Digital

Black

500GB~4TB

SATA

6 Gb/s

3.5 inch

7,200

64

N/A

None

None

Not Recommen

ded

for RAID

RoHS

Compliant

N/A

None

None PCs and High‐

Perform

ance

Work Stations

Green

500GB~6TB

5,400

RoHS Compliant and

Halogen‐Free

Desktop

and All‐in‐

one PCs

Purple

1TB

~4TB

24/7

Up to 32

Up to 8

1,000,000

N/A

Thermal

Extended

Test Passed

NVR

Surveillance

Se

1TB

~4TB

SATA

6 Gb/s

3.5 inch

7,200 64 ~ 128

24/7

Enhanced RAFF tech

64

6 +

RoHS Compliant and Halogen Red

uced

1,200,000

Self‐Encrypting Drive

Thermal Exten

ded

Test Passed

Bulk Cloud

Storage,

NAS,

Backup and

Archive

Re

250GB~4TB

SATA

& SAS

6Gb/s

32 ~ 64

Unlim

ited

Data Cen

ter

and Cloud

Storage

Xe

300~900GB

SAS 6Gb/s

2.5

inch

10,000

32

N/A

N/A

2,000,000

Enterprise

Server and

Storage

Application

Brand/M

odel

Feature

Capacity

Interface

Form

Factor

RPM

Cache (M

B)

Reliability

Vibration Protection

Cam

eras Supported

Drive Bays Supported

Environmen

tally Responsible

Mean Tim

e Before Failure

(MTB

F)/Hours

Security

Thermal Options

Ideal For

20

HDD Capacity Selector

There are a few easy-to-use capacity selector tools around, to help suggest how much

surveillance storage may be needed based on specific surveillance requirements.

1. NVR Storage Calculator i. Resource:

http://www.supercircuits.com/resources/tools/security-nvr-storage-calculator

ii. Used Parameters: Camera Stream Camera Resolution Video Quality Average Frame Size Number of Cameras Frame Rate per Camera Hours Each Camera Will Record Desired Days of Storage per Camera Bandwidth Required

2. WD Capacity Selector i. Resource:

http://www.wdc.com/en/products/products.aspx?id=1210

ii. Used Parameters Number of Cameras Days to Store Video Format Resolution Frame per Second

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Some Practical Notes

IPVM.com website regularly reveals some notes and best practices via expert surveys and investigations. Following notes are extracted from recent researches and expert opinions.

Downsides of using large size HDD

The first obvious one is about failing. The amount of video evidence loss is significantly

more.

RAID overhead. By a RAID-5 configuration you lose the capacity of one drive. 8 x 4TB

will yield roughly 28TB at RAID-5, whereas the same configuration using 16 x 2TB drives

will give you 30TB useable.

The higher HDD size, the lower total performance.

WD and Seagate review by IPVM

WD claims its Purple series HDD are more applicable and optimized for surveillance. However

for more than 32 HD cameras, they recommend their Se and Re series.

According to “IPVM favorite hard drive survey”, most preferable WD HDD for video

surveillance is the Black type. By contrast on Seagate side, their SV35 was the most frequently

cited surveillance drive for integrators.

According to the survey, most strong reasons to pick WD Black type for video surveillance

are:

Best reliability

Less than 3% failure rate

24/7 constant usage

Cost efficiency

10K RPM

And, reasons to pick Seagate for the required purpose are:

Performance

Reliability

Professional Security

Documents

for Network Video RecorderSeagate Technology ... Hard drives in a CCTV digital recorder or NVR continually write to themselves 24/7. The average hard drive you buy from a retail store