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Table of Contents



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Requirements for the bandwidth of the TCP/IP

...

network for video

...

transmission

Network bandwidth is a limiting factor in the performance of a distributed system. The transmitted information Throughput capacity of the network refers to the factors restricting performance of the distributed network. Data exchange flow is primarily made up of image video data. For instance, where surveillance cameras are used example, when you use cameras to monitor remote objects, likes such as ATMs, the data flow (image flowentire information stream (video stream) is transmitted over communication linkschannels.

In order to calculate To determine the required bandwidth of the TCP/IP network for transmitting video transmission from IP devices and some certain video capture cards, it is recommended to use the we recommend using the AxxonSoft Platform Calculator, available here (the Summary stream from ip devices IP cameras (Mbit/s) parameter). For video capture cards that are not supported by the platform calculator, use the calculation data below.

Table The table below shows the maximum number of remote surveillance cameras as a function of the throughput capacity depending on the bandwidth of various communication links. The channels. For calculation purposes, the frame rate of the image flow (reference video stream (the original format is PAL) for calculation purposes was accepted as is assumed to be equal to 1 frame per secondFPS.

Info
titleNote

In real conditions, the fluctuations of camera streams can be quite significant, depending on the scene illumination, the use of day/night mode, and how much motion there is in the frame. To accurately calculate the required network bandwidth, it is necessary to measure the stream from cameras that are already installed on the protected facility.

Communication mode

Link capacityChannel bandwidth

Black and white image

Color image



standardStandard

highHigh

fullFull

standardStandard

highHigh

fullFull

Dial-Up

56 Kbkbit/secs

<1*

<1*

<1*

<1*

<1*

<1*

ADSL, Ethernet

128 Kbkbit/secs

1

<1*

<1*

<1*

<1*

<1*

ADSL, Ethernet

256 Kbkbit/secs

2

1

1

1

1

<1*

ADSL, Ethernet

512 Kbkbit/secs

4

3

2

3

3

2

ADSL, Ethernet

1 MbMbit/secs

7

5

4

6

5

4

ADSL, Ethernet

1.5 MbMbit/secs

11

8

6

10

8

6

Ethernet

2 MbMbit/secs

14

11

8

13

10

8

Ethernet

10 MbMbit/secs

71

53

39

64

51

38

Ethernet

100 MbMbit/secs

711

533

388

640

512

376

Ethernet

1 GbGbit/secs

7282

5461

3972

6554

5243

3855

...

*

...

no more than one

...

camera, provided that maximum compression and/or additional

...

decimation is applied.

To calculate the maximum number of remote cameras transmitting image flow that transmit video to the network with a rate over 1 f/secFPS, the corresponding value shown in the table should must be divided by the number of frames.

Example: To transmit live video, a 100 Mb/sec network should be used (25 frame/sec – PAL), video image – color; frame resolution – standard. As the table shows, the Mb/sec link can transmit the image flow at a rate of 1f/sec, specified color grade and resolution from max. 640 surveillance cameras. Consequently, if the image flow rate is 25 frames per second. Live video (25 FPS—PAL) must be transmitted over a 100-megabit network. The video image is color, and the frame resolution is standard. According to the table, a 100-Mbps channel can transmit a video stream at 1 FPS and the specified color and resolution parameters from a maximum of 640 cameras. Therefore, with a video stream rate of 25 FPS, the maximum number of cameras will decrease by 25 times and will be equal to: is reduced by a factor of 25, to 640/25 = 25 cameras.

Info
titleNote
More often than not, video signal

In most cases, processing,

transfer

transmitting, and recording

requirements take up only

audio signals requires a small

proportion

amount of resources of the digital video surveillance system

resources. While calculating

. When you calculate the performance of the video surveillance system, the proportion of resources

, consumed by

allocated to audio monitoring

, may

can be neglected.

Requirements for the bandwidth of the TCP/IP network

...

for database synchronization

...

If the Axxon PSIM software operates in the distributed environment where several Servers a distributed configuration that combines several servers and/or Remote Admin Workstations are combined remote administrator workstations, the Configuration databases database synchronization is performing performed (see Configuring database synchronization).

The fulfilling of following minimal requirements for network is needed for correct synchronization of Configuration databases:

For the synchronization of the Configuration database to work correctly, the following minimum network requirements must be met:

  1. The minimum speed of data transmission over the communication channel (bandwidthMinimal speed of data transferring by link channel (capacity) is 64 kbit/secs.
  2. Maximal delay while packet transferring The maximum packet transmission delay is 500 milliseconds.

With more badly parameters value the correct operation of databases synchronization functionality worse parameter values, correct database synchronization is not guaranteed.

Requirements

...

for the TCP/IP network quality

The following connection quality requirements are imposed applied for the Axxon PSIM software video subsystem to work correctly when connecting IP devices via WAN:

  1. Latency:- for

    • For live video, no more than 10 seconds. If this value is exceeded, the connection to the IP device

    will be

    • is terminated

    ;

    • .

    - for

    • For face recognition, no more than 1500 milliseconds

    , if

    • . If this value is exceeded, many faces

    will be

    • are missed due to the skipping of a large number of frames

    ;

    • .

    - for

    • For service and smart

    detection tools

    • detectors, no more than 400 milliseconds

    , if

    • . If this value is exceeded, the quality of object detection

    will decrease

    • decreases,

    smart detection tools may incorrectly generate alarms

    • and smart detectors can generate events incorrectly.

  2. Packet loss:- for

    • For live video, no more than 40%. If this value is exceeded, the connection to the camera

    will be

    • is terminated. With a packet loss of 10% to 40%,

    frame drops will be observed

    • frames are skipped (the more losses, the more

    drops

    • skips)

    ;

    • .

    - for

    • For face recognition, service and smart

    detection tools

    • detectors, no more than 25%. If this value is exceeded,

    skipping of faces will be missed

    • faces are skipped, and the tracks of smart

    detection tools will not

    • detectors don't correspond to objects.