Moxa Technologies VPort 2140 Network Card User Manual


 
Troubleshooting
Q: Why can’t I watch video from Video Server after it is authenticated?
A: There are many possible scenarios regarding this problem,
1. If you have just installed Video Server and are unable to watch the video, check if the video
input is enabled and check the video modulation on the Configuration page.
2. If Video Server is installed correctly and you are accessing Video Server for the first time
using Internet Explorer, adjust the security level of Internet Explorer to allow installation of
the plug-in.
3. If the problem still exists after making the adjustment, the current number of users may be
greater than what the system allows.
4. If you are using a demo account, the administrator may hide the video from public view.
Q: How can I use a name instead of the IP address to connect Video Server?
A: To allow users to connect to Video Server through an easily memorized name, administrators
must first configure the network’s domain name server. Here is an example: the administrator
installs the Video Server with a reserved IP address and assigns it a name on the domain name
service, then users can connect to Video Server by typing a name instead of an IP address. If
there is DHCP service on the network, the IP address must be excluded on the DHCP service to
prevent an IP conflict.
Q: What is the plug-in for?
A: The plug-in provided by Video Server is used to display motion pictures on versions of Internet
Explorer that do not support server push technology. If your system does not allow installation
of any plug-in software, the security level of the web browser may need to be lowered. It is
recommended that you consult the network supervisor in your office regarding adjusting the
security level.
Q: Why is the timestamp different from the system time of my PC or notebook?
A: The timestamp is based on the system time of Video Server. It is maintained by an internal
real-time clock, and automatically synchronizes with the time server if Video Server is
connected to the Internet and the function is enabled. Differences of several hours may result
from the time zone setting.
Q: Why does the image not refresh regularly?
A: In a modem environment, it is because the bandwidth of PPP connections is much lower than
for Ethernet. If the difference of the timestamp is not stable, use the modem property on the
control panel to adjust the UART FIFO to a lower level for both receiving and transmitting. In
an Ethernet environment, it may be due to the time taken for storing snapshots into memory
when events occur.
Q: How many users are allowed to watch Video Server at the same time?
A: To achieve the best effect, Video Server will allow a maximum of twenty users to connect at
the same time. Excess users can get an auto-refreshed still image on homepage instead. It is
recommended to build another web server to host a large quantity of users by retrieving images
from Video Server periodically.
Q: How fast is the video rate of Video Server?
A: The JPEG codec can process 30 frames per second internally. However, the overall
performance is subject to many different factors, such as:
1. network throughput,
2. bandwidth share,
3. number of users,
4. number of video inputs accessed at one time,
5. viewing complicated objects results in a larger image file,
6. the level of your PC or notebook that is responsible for displaying images.
In general, the transfer rate on a general local network environment can achieve over 200
Kbytes per second and approximately 10 to 20 pictures of normal environment per second. The
general frame size is illustrated in the following table for your reference.
VPort 2140 User’s Manual
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