9.
Technical
Specification
AirLive POE-260CAM User’s Manual
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A proxy server receives requests for Internet services (such as web page requests)
from many users. If the proxy server is also a cache server, it looks in its local cache of
previously downloaded web pages. If it finds the page, it is returned to the user without
forwarding the request to the Internet. If the page is not in the cache, the proxy server,
acting as a client on behalf of the user, uses one of its own IP addresses to request the
page from another server over the Internet. When the requested page is returned, the
proxy server forwards it to the user that originally requested it.
PTZ -
Pan, tilt and zoom.
Resolution -
Image resolution is a measure of how much detail a digital image can hold: the greater
the resolution, the greater the level of detail. Resolution can be specified as the
number of pixel-columns (width) by the number of pixel-rows (height), for example,
320x240.
Alternatively, the total number of pixels (usually in megapixels) in the image can be
used. In analog systems it is also common to use other format designations, such as
CIF, QCIF, 4CIF, etc.
RTCP (Real-Time Control Protocol) -
RTCP provides support for real-time conferencing of groups of any size within an
intranet. This support includes source identification and support for gateways like
audio and video bridges as well as multicast-to-unicast translators.
RTCP offers quality-of-service feedback from receivers to the multicast
group as well as support for the synchronization of different media streams.
RTP (Real-Time Transport Protocol) -
RTP is an Internet protocol for the transport of real-time data, for example, audio and
video. It can be used for media-on-demand as well as interactive services such as
Internet telephony.
RTSP (Real Time Streaming Protocol) -
RTSP is a control protocol, and a starting point for negotiating transports such as RTP,
multicast and Unicast, and for negotiating codecs.
RTSP can be considered a "remote control" for controlling the media stream delivered
by a media server. RTSP servers typically use RTP as the protocol for the actual
transport of audio/video data.
