Axis Communications 210 User Manual

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Glossary of Terms
 
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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.