Axis 242, Руководство пользователя

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AXIS 242S IV - Glossary
VPN (Virtual Private Network) - This creates a secure
"tunnel" between the points within the VPN. Only devices
with the correct "key" will be able to work within the
VPN. The VPN network can be within a company LAN
(Local Area Network), but different sites can also be
connected over the Internet in a secure way. One common
use for VPN is for connecting a remote computer to the
corporate network, via e.g. a direct phone line or via the
Internet.
VOP (Video Object Plane) - A VOP is an image frame in
an MPEG-4 video stream. There are several types of VOP:
- An I-VOP is a complete image frame.
- An P-VOP codes the differences between images, as long
as it is more efficient to do so. Otherwise it codes the
whole image, which may also be a completely new image.
WAN (Wide-Area-Network) - Similar to a LAN, but on a
larger geographical scale.
W-LAN (Wireless LAN) - A wireless LAN is a wireless
local area network that uses radio waves as its carrier:
where the network connections for end-users are wireless.
The main network structure usually uses cables.
Web camera (Webcam) -
A camera that requires a
constant connection (via e.g. USB) to a PC for its
operation. See also
Network camera .
Web server - A program that allows web browsers to
retrieve files from computers connected to the Internet.
The Web server listens for requests from browsers and
upon receiving a request for a file sends it back to the
browser. The primary function of a Web server is to serve
pages to other remote computers.
WEP (Wireless Equivalent Privacy) - A wireless security
protocol, specified in the IEEE 802.11 standard, which is
designed to provide a wireless local area network (WLAN)
with a level of security and privacy comparable to that
usually expected of a wired LAN. Security is at two
different levels; 40-bit and 128-bit encryption. The higher
the bit number, the more secure the encryption.
WINS (Windows Internet Naming Service) - Part of the
Microsoft Windows NT Server, WINS manages the
association of workstation names and locations with IP
addresses, without the user or administrator having to be
involved in each configuration change.
WPA-PSK (Wi-Fi Protected Access - Pre-Shared Key)
-
This wireless encryption method uses a pre-shared key
(PSK) for key management. Keys can usually be entered as
manual hex values, as hexadecimal characters, or as a
Passphrase. WPA-PSK provides a greater degree of
security than WEP.
Zoom lens
- A zoom lens can be moved (zoomed) to
enlarge the view of an object to show more detail.