ALIEN MEGA/MAX USER MANUAL
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Chapter 13 Glossary
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Dual Stream:
Dual stream is a technology used to record high resolution video
locally while transmitting a lower resolution stream over the network. The two
streams are generated by the DVR, with the main stream having a maximum
resolution of 1080P and the sub-stream having a maximum resolution of CIF.
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DVR:
Acronym for Digital Video Recorder. A DVR is device that is able to
accept video signals from analog cameras, compress the signal and store it on its
hard drives.
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HDD:
Acronym for Hard Disk Drive. A storage medium which stores digitally
encoded data on platters with magnetic surfaces.
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DHCP:
Dynamic Host Configuration Protocol (DHCP) is a network application
protocol used by devices (DHCP clients) to obtain configuration information for
operation in an Internet Protocol network.
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HTTP:
Acronym for Hypertext Transfer Protocol. A protocol to transfer
hypertext request and information between servers and browsers over a network
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PPPoE:
PPPoE, Point-to-Point Protocol over Ethernet, is a network protocol for
encapsulating Point-to-Point Protocol (PPP) frames inside Ethernet frames. It is
used mainly with ADSL services where individual users connect to the ADSL
transceiver (modem) over Ethernet and in plain Metro Ethernet networks.
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DDNS:
Dynamic DNS is a method, protocol, or network service that provides
the capability for a networked device, such as a router or computer system using
the Internet Protocol Suite, to notify a domain name server to change, in real
time (ad-hoc) the active DNS configuration of its configured hostnames,
addresses or other information stored in DNS.
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Hybrid DVR:
A hybrid DVR is a combination of a DVR and NVR.
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NTP:
Acronym for Network Time Protocol. A protocol designed to synchronise
the clocks of computers over a network.
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NTSC:
Acronym for National Television System Committee. NTSC is an
analogue television standard used in such countries as the United States and
Japan. Each frame of an NTSC signal contains 525 scan lines at 60Hz.
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NVR:
Acronym for Network Video Recorder. An NVR can be a PC-based or
embedded system used for centralised management and storage for IP cameras,
IP Domes and other DVRs.
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PAL:
Acronym for Phase Alternating Line. PAL is also another video standard
used in broadcast televisions systems in the UK and large parts of the world.
PAL signal contains 625 scan lines at 50Hz.
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PTZ:
Acronym for Pan, Tilt, Zoom. PTZ cameras are motor driven systems that
allow the camera to pan left and right, tilt up and down and zoom in and out.
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USB:
Acronym for Universal Serial Bus. USB is a plug-and-play serial bus
standard to interface devices to a host computer.
