Axis Communications 210A - Manual (Page 60)

Glossary of Terms
60 AXIS 210/210A/211/211A - Glossary of Terms
Active Speaker - a speaker with a built-in power amplifier.
ActiveX - A control (or set of rules) used by a browser.
ActiveX controls are often downloaded and installed
automatically as required.
ADPCM - Adaptive Differential Pulse Code Modulation.
Predicts the analog signal digitally and the difference is
coded.
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 for assigning
an IP address to a physical device address that is recognized
in the local network. The ARP command can be used to set
the IP-address for your product.
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.
dB (Decibels) - A unit to measure sound level changes. A
3dB change is the smallest level change we can hear. A 3dB
change is actually twice or half the audio power level. A
gain of 0dB will leave the signal level unchanged.
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.
G.711 - G.711 is the international standard for encoding
telephone audio on 64 kBit/s channel. It is a pulse code
modulation (PCM) scheme operating at 8 kHz sample rate.
G.726 - Frequently used speech-compression algorithm in
telecommunications due to its high perceived speech quality
and low resource requirements.
Half duplex- A half duplex link can communicate in only
one direction, at a time. Two way communication is
possible, but not simultaneously. Walkie-talkies and CB
radios mimic this behavior in that you cannot hear the other
person if you are talking.
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 standard video format, used for low bandwidth
video streams.
Multicast - The same information is sent only once and
only to the intended recipients.
NTSC - National Television Standards Committee. NTSC is
the standard format used for televisions in most of North
and Central America, and Japan.