An Internet protocol camera, or IP camera, is a type of digital video camera commonly
employed for surveillance, and which unlike analog closed circuit television cameras can
send and receive data via a computer network and the Internet.
Although most cameras that do this are webcams, the term "IP camera" or "netcam" is usually
applied only to those used for surveillance.
The first centralized IP camera was Axis Neteye 200, released in 1996 by Axis Communications.
There are two kinds of IP cameras: Centralized IP cameras, which require a central
Network Video Recorder(NVR) to handle the recording, video and alarm management.
Decentralized IP cameras, which do not require a central Network Video Recorder, as the cameras
have recording function built-in and can thus record directly to any standard storage media,
such as SD cards, NAS or a PC/Server.
History The first centralized IP camera was released
in 1996 by Axis Communications.
It was called the Axis Neteye 200 and was developed by the team of Martin Gren and Carl-Axel
Alm.
It used a custom web server internal to the camera.
In late 1999, the company started using embedded Linux to operate its cameras.
Axis also released documentation for its low-level API called "VAPIX", which builds on the open
standards of HTTP and real time streaming protocol.
This open architecture was intended to encourage third-party software manufacturers to develop
compatible management and recording software.
The first decentralized IP camera was released in 1999 by Mobotix.
The camera's Linux system contained video, alarm, and recording management function,
thus the camera system did not require licensed video management software to manage the recording
event, or video management.
The first IP camera with onboard video content analytics was released in 2005 by Intellio.
This camera was able to detect a number of different events, such as if an object was
stolen, a human crossed a line, a human entered a predefined zone, or if a car moved in the
wrong direction.
IP cameras are available at resolutions from 0.3 to 29 megapixels.
As in the consumer TV business, in the early 21st century, there has been a shift towards
high-definition video resolutions, e.g. 720p or 1080i and 16:9 widescreen format.
Standards Analog closed circuit television uses established
broadcast television formats, NTSC, PAL, and SECAM).
Generally speaking, each make of IP camera will differ in its features and functions,
video encoding schemes, available network protocols, and the API to be used by video
management software.
In order to address issues of standardization of IP video surveillance, two industry groups
were formed in 2008: the Open Network Video Interface Forum and the Physical Security
Interoperability Alliance.
While the PSIA was founded by 20 member companies including Honeywell, GE Security and Cisco,
and ONVIF was founded by Axis Communications, Bosch and Sony, each group now has numerous
members.
As of January 2009, each group had released version 1.0 of their specification.
Potential advantages Two-way audio via a single network cable allows
users to communicate with what they are seeing Flexibility: IP cameras can be moved around
anywhere on a network.
Distributed intelligence: with IP cameras, video analytics can be placed in the camera
itself allowing ability in analytics solutions.
Transmission of commands for PTZ cameras via a single network.
Encryption & authentication: IP cameras offer secure data transmission through encryption
and authentication methods such as WPA, WPA2, TKIP, AES.
Remote accessibility: live video from selected cameras can be viewed from any computer, anywhere,
and also from many mobile smartphones and other devices.
Remote accessibility also prevents police officers from confiscating video and audio
evidence that you can use against them IP cameras are able to function on a wireless
network.
PoE - Power over Ethernet: Modern IP cameras have the ability to operate without a power
supply.
They can work with the PoE-protocol.
IP camera communication signals are not just electronic voltage, it is numerically decoded
as bits and bytes with security features and TCP/IP protocol.
Potential disadvantages Higher initial cost per camera, except where
cheaper webcams are used.
High network bandwidth requirements: a typical CCTV camera with resolution of 640x480 pixels
and 10 frames per second in MJPEG mode requires about 3 Mbit/s.
As with a CCTV/DVR system, if the video is transmitted over the public Internet rather
than a private IP LAN, the system becomes open to a wider audience of hackers and hoaxers.
Criminals can hack into a CCTV system to observe security measures and personnel, thereby facilitating
criminal acts and rendering the surveillance counterproductive.
See also Closed-circuit television camera
TCP/IP References