Axis 212 PTZ-V [52/57] Axis 212 ptz v glossary of terms
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Axis 212 PTZ-V [52/57] Axis 212 ptz v glossary of terms

Axis 212 PTZ-V [52/57] Axis 212 ptz v glossary of terms
AXIS 212 PTZ/-V - Glossary of Terms
easier to remember than 192.0.34.166. The translation tables for
domain names are contained in Domain name servers.
Domain Server - Domains can also be used by organizations who wish
to centralize the management of their (Windows) computers. Each user
within a domain has an account that usually allows them to log in to
and use any computer in the domain, although restrictions may also
apply. The domain server is the server that authenticates the users on
the network.
Duplex - See Full-duplex.
Ethernet - Ethernet is the most widely installed local area network
technology. An Ethernet LAN typically uses special grades of twisted
pair wires. The most commonly installed Ethernet systems are 10BASE-T
and 100BASE-T10, which provide transmission speeds up to 10 Mbps
and 100 Mbps respectively.
ETRAX (Ethernet Token Ring AXIS) - Axis' own microprocessor.
Factory default settings - These are the settings that originally
applied for a device when it was first delivered from the factory. If it
should become necessary to reset a device to its factory default
settings, this will, for many devices, completely reset any settings that
were changed by the user.
Firewall - A firewall works as a barrier between networks, for example,
between a Local Area Network and the Internet. The firewall ensures
that only authorized users are allowed to access the one network from
the other. A firewall can be software running on a computer, or it can
be a standalone hardware device.
Focal length - Measured in millimeters, the focal length of a camera
lens determines the width of the horizontal field of view, which in turn
is measured in degrees.
FTP (File Transfer Protocol) - An application protocol that uses the
TCP/IP protocols. It is used to exchange files between
computers/devices on networks.
Frame - A frame is a complete video image. In the 2:1 interlaced
scanning format of the RS-170 and CCIR formats, a frame is made up of
two separate fields of 262.5 or 312.5 lines interlaced at 60 or 50 Hz to
form a complete frame, which appears at 30 or 25 Hz. In video cameras
with a progressive scan, each frame is scanned line-by-line and not
interlaced; most are also displayed at 30 and 25 Hz.
Frame rate - The frame rate used to describe the frequency at which a
video stream is updated is measured in frames per second (fps). A higher
frame rate is advantageous when there is movement in the video
stream, as it maintains image quality throughout.
Full-duplex - Transmission of data in two directions simultaneously. In
an audio system this would describe for example, a telephone systems.
Half-duplex also provides bi-directional communication, but only in one
direction at a time, as in a walkie-talkie system. See also Simplex.
Gain - Gain is the amplification factor and the extent to which an
analog amplifier boosts the strength of a signal. Amplification factors
are usually expressed in terms of power. Decibel (dB) is the most
common way of quantifying the gain of an amplifier.
Gateway - A gateway is a point in a network that acts as an entry
point to another network. In a corporate network for example, a
computer server acting as a gateway often also acts as a proxy server
and a firewall server. A gateway is often associated with both a router,
which knows where to direct a given packet of data that arrives at the
gateway, and a switch, which furnishes the actual path in and out of the
gateway for a given packet.
GIF (Graphics Interchange Format) - GIF is one of the most common
file formats used for images in web pages. There are two versions of the
format, 87a and 89a. Version 89a supports animations, i.e. a short
sequence of images within a single GIF file. GIF89a can also be specified
for interlaced presentation.
GOV (Group Of VOPs) -
A group of VOPs is the basic unit of an
M
PEG-4 video stream. The GOV contains different types and numbers of
VOPs (I-VOPs, P-VOPs, etc.) as determined by the GOV length and GOV
structure. See also VOP.
GOV length - The GOV length determines the number of images (VOPs)
in the GOV structure. See also GOV and VOP.
GOV structure - The GOV structure describes the composition of an
MPEG-4 video stream, as regards the type of images (I-VOPs or P-VOPs)
included in the stream, and their internal order. See also GOV and VOP.
Half-duplex - See Full-duplex.
HTML (Hypertext Markup Language) - HTML is the set of “markup”
symbols or codes inserted in a file intended for display in web browser.
The markup tells the browser how to display the page's words and
images for the user.
HTTP (Hypertext Transfer Protocol) - HTTP is the set of rules for
exchanging files (text, graphic images, sound, video, and other
multimedia files) on the web. The HTTP protocol runs on top of the
TCP/IP suite of protocols.
Hub - A (network) hub is used to connect multiple devices to the
network. The hub transmits all data to all devices connected to it,
whereas a switch will only transmit the data to the device it is
specifically intended for.
IEEE 802.11 - A family of standards for wireless LANs. The 802.11
standard supports 1 or 2 Mbit/s transmission on the 2.4 GHz band. IEEE
802.11b specifies an 11 Mbit/s data rate on the 2.4 GHz band, while
802.11a allows up to 54 Mbit/s on the 5 GHz band.
Image compression - Image compression minimizes the file size (in
bytes) of an image. Two of the most common compressed image formats
are JPEG and GIF.
Interlacing - Interlaced video is video captured at 50 pictures (known
as fields) per second, of which every 2 consecutive fields (at half height)
are then combined into 1 frame. Interlacing was developed many years
ago for the analog TV world and is still used widely today. It provides
good results when viewing motion in standard TV pictures, although
there is always some degree of distortion in the image.
To view interlaced video on for example, a computer monitor, the video
must first be de-interlaced, to produce progressive video, which consists
of complete images, one after the other, at 25 frames per second. See
also Progressive scan.
IP (Internet Protocol) - The Internet Protocol is a method transmitting
data over a network. Data to be sent is divided into individual and
completely independent “packets.” Each computer (or host) on the
Internet has at least one address that uniquely identifies it from all
others, and each data packet contains both the sender's address and the
receiver's address.
The Internet Protocol ensures that the data packets all arrive at the

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