Below is general information on surveillance camera technologies, their differences, and some of the pro’s and con’s of IP solutions:
History of CCTV
The first CCTV system was installed by Siemens AG at Test Stand VII in Peenemünde, Germany in 1942, for observing the launch of V-2 rockets. The noted German engineer Walter Bruch was responsible for the technological design and installation of the system. CCTV recording systems are still often used at modern launch sites to record the flight of the rockets, in order to find the possible causes of malfunctions, while larger rockets are often fitted with CCTV allowing pictures of stage separation to be transmitted back to earth by radio link.
The earliest systems required constant monitoring because there was no way to record and store the information. Recording systems would be introduced later, when primitive reel-to-reel media was used to preserve the data, where the magnetic tapes had to be changed manually. It was a time consuming, expensive and unreliable process; the operator had to manually thread the tape from the tape reel through the recorder onto an empty take-up reel. Due to these efforts, video surveillance was rare. Only when VCR technology became available in the 1970′s, which made it easy to record and erase information, did video surveillance start to become much more common.
During the 1980′s video surveillance began to spread across the country specifically targeting public areas. It was seen as a cheaper way to deter crime compared to increasing the size of the police departments. Some businesses as well, especially those that were prone to theft, began to use video surveillance.
During the 1990′s digital multiplexing, which allowed for several cameras at once to record, and introduced time lapse and motion only recording, increased the use of CCTV across the country, and increased the savings of time and money. From the mid-1990′s on, police departments across the country installed an increasing number of cameras in various public spaces including housing projects, schools and public parks departments. Following the September 11 attacks, the use of video surveillance has become a common occurrence in the country. CCTV has become very common in banks and stores to discourage theft, by recording evidence of criminal activity. In recent decades, especially with general crime fears growing in the 1990′s and 2000′s, public space use of surveillance cameras has grown exponentially.
The History of IP Cameras
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 (RTSP). 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 on-board video content analytic’s (VCA) 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 (VGA resolution) 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.
IP Camera Standards
Analog closed circuit television uses established broadcast television formats (e.g. Common Intermediate Format (CIF), NTSC, PAL, and SECAM). Generally speaking, each make of IP camera will differ in its features and functions, video encoding (compression) 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 (ONVIF) and the Physical Security Interoperability Alliance (PSIA). 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 of IP Cameras
- Two-way audio via a single network cable allows users to communicate with what they are seeing (e.g. gas station clerk assisting a customer on how to use the prepay pumps)
- Flexibility: IP cameras can be moved around anywhere on an IP network (including wireless).
- Distributed intelligence: with IP cameras, video analytic’s can be placed in the camera itself allowing scale-able analytic’s solutions.
- Transmission of commands for PTZ (pan, tilt, zoom) cameras via a single network cable.
- Encryption & authentication: IP cameras offer secure data transmission through encryption and authentication methods such as WEP, 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.
- IP cameras are able to function on a wireless network.
- PoE – Power over Ethernet: Modern IP cameras have the ability to operate without an additional power supply. They can work with the PoE-protocol which gives power via the Ethernet cable.
Potential disadvantages of IP Cameras
- Higher initial cost per camera
- High network bandwidth requirements
- 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.
ACCESS CONTROL SYSTEM OVERVIEW
The term access control refers to the practice of restricting entrance to a property, a building, or a room to authorized persons. Physical access control can be achieved through technological means such as access control systems. Electech is the team of professionals you need to help you chose the right product for your application. We constantly explore more innovative and cost effective solutions to provide the best solutions.
Physical access control is a matter of who, where, and when. An access control system determines who is allowed to enter or exit, where they are allowed to exit or enter, and when they are allowed to enter or exit. Historically, this was partially accomplished through keys and locks. When a door is locked, only someone with a key can enter through the door, depending on how the lock is configured. Mechanical locks and keys do not allow restriction of the key holder to specific times or dates. Mechanical locks and keys do not provide records of the key used on any specific door, and the keys can be easily copied or transferred to an unauthorized person. When a mechanical key is lost or the key holder is no longer authorized to use the protected area, the locks must be re-keyed. Cost of personnel changes are greatly increased.
Electronic access control uses computer boards to solve the limitations of mechanical locks and keys. A wide range of credentials can be used to replace mechanical keys. The electronic access control system grants access based on the credential presented. When access is granted, the door is unlocked for a predetermined time and the transaction is recorded. When access is refused, the door remains locked and the attempted access is recorded. The system will also monitor the door and alarm if the door is forced open or held open too long after being unlocked.
ACCESS CONTROL SYSTEM OPERATION
When a credential is presented to a reader, the reader sends the credential’s information, usually a number, to a control panel, a highly reliable processor. The control panel compares the credential’s number to an access control list, grants or denies the presented request, and sends a transaction log to a database. When access is denied based on the access control list, the door remains locked. If there is a match between the credential and the access control list, the control panel operates a relay that in turn unlocks the door. The control panel also ignores a door open signal to prevent an alarm. Often the reader provides feedback, such as a flashing red LED for an access denied and a flashing green LED for an access granted.
The above description illustrates a single factor transaction. Credentials can be passed around, thus subverting the access control list. For example, Alice has access rights to the server room, but Bob does not. Alice either gives Bob her credential, or Bob takes it; he now has access to the server room. To prevent this, two-factor authentication can be used. In a two factor transaction, the presented credential and a second factor are needed for access to be granted; another factor can be a PIN, a second credential, operator intervention, or a bio-metric input.
- something the user knows, e.g. a password, pass-phrase or PIN
- something the user has, such as smart card or a key fob
- something the user is, such as fingerprint, verified by bio-metric measurement
Passwords are a common means of verifying a user’s identity before access is given to information systems. In addition, a fourth factor of authentication is now recognized: someone you know, whereby another person who knows you can provide a human element of authentication in situations where systems have been set up to allow for such scenarios. For example, a user may have their password, but have forgotten their smart card. In such a scenario, if the user is known to designated cohorts, the cohorts may provide their smart card and password, in combination with the extant factor of the user in question, and thus provide two factors for the user with the missing credential, giving three factors overall to allow access.
A credential is a physical/tangible object, a piece of knowledge, or a facet of a person’s physical being, that enables an individual access to a given physical facility or computer-based information system. Typically, credentials can be something you know (such as number or PIN), something you have (such as an access badge), something you are (such as a bio-metric feature) or some combination of these items. The typical credential is an access card, key-fob, or other key. There are many card technologies including magnetic stripe, bar code, Wiegand, 125 kHz proximity, 26-bit card-swipe, contact smart cards, and contact-less smart cards. Also available are key-fobs, which are more compact than ID cards, and attach to a key ring. Typical bio-metric technologies include fingerprint, facial recognition, iris recognition, retinal scan, voice, and hand geometry.
ACCESS CONTROL SYSTEM COMPONENTS
An access control point, which can be a door, turnstile, parking gate, elevator, or other physical barrier, where granting access can be electronically controlled. Typically, the access point is a door. An electronic access control door can contain several elements. At its most basic, there is a stand-alone electric lock. The lock is unlocked by an operator with a switch. To automate this, operator intervention is replaced by a reader. The reader could be a keypad where a code is entered, it could be a card reader, or it could be a bio-metric reader. Readers do not usually make an access decision, but send a card number to an access control panel that verifies the number against an access list. To monitor the door position a magnetic door switch can be used. In concept, the door switch is not unlike those on refrigerators or car doors. Generally only entry is controlled, and exit is uncontrolled. In cases where exit is also controlled, a second reader is used on the opposite side of the door. In cases where exit is not controlled, free exit, a device called a request-to-exit (REX) is used. Request-to-exit devices can be a push-button or a motion detector. When the button is pushed, or the motion detector detects motion at the door, the door alarm is temporarily ignored while the door is opened. Exiting a door without having to electrically unlock the door is called mechanical free egress. This is an important safety feature. In cases where the lock must be electrically unlocked on exit, the request-to-exit device also unlocks the door.