When only MPEG4 images are distributed, the maximum number of distributions is determined by the preset bit rate. When a distribution request that exceeds the maximum number of distributions is received, this request is denied.

When distributing only MPEG4 data

Preset bit

Maximum

Total

number of

maximum bit

rate

distributions

rate

 

 

 

 

0.6 Mbps

20

12 Mbps

and below

 

 

 

 

 

3 Mbps and

4

12 Mbps

below

 

 

 

 

 

6 Mbps and

2

12 Mbps

below

 

 

 

 

 

Larger than

1

Maximum

6 Mbps

 

configurable

 

 

value (8

 

 

Mbps)

 

 

 

When both JPEG and MPEG4 images are distributed simultaneously, distribution up to two clients for JPEG and MPEG4 respectively is possible. However, distribution requests that exceed a total bit rate of 20 Mbps will be denied.

 

Maximum

Maximum

Total bit

number of

number of

rate

distributions

distributions

 

for JPEG

for MPEG4

 

 

 

20 Mbps and

2

2

below

 

 

 

 

 

Insufficient network bandwidth

When there is insufficient bandwidth, the number of JPEG frames (frame rate) that the client can acquire will decrease. Delay will also occur in the distribution of images. In the case of MPEG4, noise interference may occur and playback may fail.

Network Delay

When the client acquires JPEG via TCP, VN-V25U will send out data while checking the ACK from the client at the same time. For networks with considerable delay, data cannot be sent out until ACK is received, and therefore the frame rate will drop. In the case of MPEG4, noise interference may occur and playback may fail.

Decrease in the frame rate due to network delays can be eliminated by receiving data via multicast.

Network Jitter

When there is considerable network jitter, delay time may be prolonged and the image frame rate may drop. In the case of MPEG4, noise interference may occur and playback may fail.

Packet Loss

When acquiring images from VN-V25U via TCP, packet loss may be recovered by TCP transmission. When there is considerable delay in the network, however, missing data may occur and the image frame rate may drop. In the case of MPEG4, noise interference may occur and playback may fail.

When packet loss occurs during multicast sending from VN-V25U, the image frame rate may drop. In the case of MPEG4, noise interference may occur and playback may fail.

List of Protocols and Port Numbers Used by VN-V25U

VN-V25U uses the protocols and port numbers listed below. Ensure that these ports are allowed through the firewall when a firewall is to be installed.

Protocol/Port No.

Purpose of Use

 

 

Source

 

 

 

TCP/80

JPEG/MPEG4

 

acquisition, Web

 

Settings page, API

 

 

TCP/10020

(Reserved for

TCP/10021

adjustment)

TCP/10023

 

 

 

Destination

 

 

 

TCP/20, 21

FTP

 

 

TCP/25

Mail delivery

 

 

TCP/110

POP (Mail Delivery)

 

 

TCP/User Setting No.

Sending alarm

 

 

UDP/123

SNTP

 

 

UDP/User Setting No.

Sending alarm

 

 

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