Axis Communications 221 - Manual (Page 56)

AXIS COMMUNICATIONS <Product Name> Quick User’s Guide
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Glossary of Terms
ActiveX - A control (or set of rules) used by a browser.
ActiveX controls are often downloaded and installed
automatically as required.
AMC - AXIS Media Control. The control required for
viewing video images in Internet Explorer for Windows.
Installs automatically on first use.
API - Application Programming Interface. The Axis API
can be used for integrating Axis products into other
applications.
ARP - Address Resolution Protocol. A protocol used to
associate an IP address to a hardware MAC address. A
request is broadcast on the local network to find out what
the MAC address is for the IP address.
ARTPEC - Axis Real Time Picture Encoder - used for video
image compression.
CCD - Charge Coupled Device. CCD is one of the two main
types of image sensors used in digital cameras. When a
picture is taken, the CCD is struck by light coming through
the camera’s lens. Each of the thousands or millions of tiny
pixels that make up the CCD convert this light into
electrons.
CGI - Common Gateway Interface. A set of rules (or a
program) that allows a Web Server to communicate with
other programs.
Client/Server - Describes the network relationship between
two computer programs in which one, the client, makes a
service request from another - the server.
DC-Iris - This special type of iris is electrically controlled
by the Axis camera, to automatically regulate the amount
of light allowed to enter.
DNS - The Domain Name System (DNS) locates and
translates Internet domain names into IP (Internet Protocol)
addresses.
Ethernet - A widely used networking standard.
ETRAX - Axis' own microprocessor.
Firewall - A virtual barrier between a LAN (Local Area
Network) and other networks, e.g. the Internet.
FTP - File Transfer Protocol. Used for the simple transfer of
files to and from an FTP-server.
Full-duplex - Transmission of data, e.g. audio, in two
directions simultaneously.
HTML - Hypertext Mark-up Language. Used widely for
authoring documents viewed in web browsers.
HTTP - Hypertext Transfer Protocol. The set of rules for
exchanging files (text, images, sound, video, and other
files) on the World Wide Web.
HTTPS - Hypertext Transfer Protocol over Secure Socket Layer.
A web protocol that provides encryption for page requests from
users and for the pages returned by the web server.
Intranet - A private network limited to an organization or
corporation. Usually closed to external traffic.
IP - Internet-Protocol. See TCP/IP.
IP address - A unique number used by a network device, to
allow it to be identified and found on the network. The 32-bit
IP address is made up of four groups (or quads) of decimal
digits separated by periods. An example of an IP address is:
192.168.0.1
ISMA - Internet Streaming Media Alliance
JPEG - A standard image format, used widely for photographs.
Also known as JPG.
LAN - A local area network (LAN) is a group of computers and
associated devices that typically share common resources
within a limited geographical area.
Linux - A popular operating system, which is “open source”
and practically free of charge.
Lux - A standard unit for the measurement of light, where 1
Lux equals the light emitted from a single candle at a distance
of one meter.
Mbit/s - Megabits per second. A unit for measuring speeds in
networks. A LAN might run at 10 or 100 Mbit/s.
MPEG-4 - A video compression standard that makes good use
of bandwidth, and which can provide high-quality video
streams at less than 1 Mbit/s.
Multicast - A bandwidth-conserving technology that reduces
bandwidth usage by simultaneously delivering a single stream
of information to multiple network recipients.
NTSC - National Television Standards Committee. NTSC is the
standard format used for televisions in most of North and
Central America, and Japan.
PAL - Phase Altering Line. PAL is the standard format used for
televisions in most of the world (other than the US, Canada, and
Japan).
PEM - Privacy Enhanced Mail. An early standard for securing
electronic mail. The PEM-format is often used for representing
an HTTPS certificate or certificate request.
Ping - A small utility used for sending data packets to network
resources to check that they are working and that the network
is intact.
Pre/post alarm image - The images from immediately before
and after an alarm.
Privacy mask - An image or specified area used to block out
certain parts of the video image.
Protocol - A special set of rules governing how two entities will
communicate. Protocols are found at many levels of