Alarm is a facility that allows external alarms like PIR's, reed switches, vibration sensors etc. to be connected to the CCTV switcher so that a nominated camera is switched on when an alarm signal is received.
Complex mathematical formulae or rules used to solve problems. In video, they are used to achieve digital compression of a video picture.
Representation of data by continuously varying quantities.
Electronic circuits made up of components that can handle analogue signals. Examples: Resistors, capacitors etc.
It is a type of ISDN technology using constant size 53 byte cells instead of variable size packets. Because cells do not change size, they switch much faster and more efficiently.
Backbone is the infrastructure that is used to inter-connect the various local area networks to build a wide area network.
Bandwidth is the range of frequencies or data that pass through an electrical/electronic amplifying, processing or transmission unit without attenuation or loss.
A base 2 numbering system using two digits 0 and 1.
The short form for binary digit.
A network device that logically separates a single network into segments.
Brightness represents the intensity of illumination of the reproduced picture.
Group or word of bits. Usually has 8 bits.
An electronic device that converts light into an electrical signal.
Charge Coupled Device is a solid-state device in a camera that converts light falling on it into an electrical signal.
The Common Gateway Interface (CGI) is a standard for interfacing external applications with information servers, such as HTTP or Web servers. A CGI program can be written in any language that allows it to be executed on the system, such as: C/C++, PERL, Visual Basic etc.
The process of reducing the size of digital signal.
The ratio between the size of data before and after compression.
The process of reducing the size of digital signal.
The Central Processor Unit is the brain of a digital system like a computer, where all the manipulation or processing of digital data is done. Its speed is measured in Hertz. It also states the number of instructions it undertakes per sec.
The amount of data being handled by a device every second.
DDNS stands for Dynamic Domain Name Server: This is a service provided by different service providers, and is suitable for situations where the IP address is dynamic and keeps changing. The user registers a host name with a service provider and whenever the dynamic IP address changes, the DDNS service provider automatically updates the DNS servers all over the world.
A base 10 numbering system using ten digits 0, 1,2,3,4,5,6,7,8,9.
Dynamic Host Configuration Protocol is used in a TCP/IP protocol network to send client configuration data including TCP/IP address, subnet mask to the clients.
Domain Name Server (DNS): When the user types in 'www.panasonic.com ', the DNS server in the network converts it into an IP address, which is then used in all communications.
Digital Subscriber Line is a high-speed network connection using standard POTS or PSTN telephone cable.
Digital Signal Processing chip is like a mini computer with its own RAM, CPU and different application software. As required the software is activated to manipulate the digital signal.
This is not a permanent address and is a good solution to overcome the shortage of IP addresses. The Dynamic Host Configuration (DHCP) server allocates temporary IP addresses to the devices connected to the network. If a device logs on to the network, it is given a temporary IP address for a fixed time period or the same IP address is given to another device when the original user logs off.
A combination of hardware and software that protects the network from attack by hackers who could gain access through the public networks.
A lens with fixed focal length.
A frame is the basic unit of a moving picture. At least 24 frames per second are required for a moving picture to look continuous.
The number of completed cycles of a waveform that occurs in a given length of time. Usually specified in cycles per second (Hertz).
Frequency Range is the number of different frequencies that are included in the analogue signal Usually specified in cycles per second (Hertz).
File Transfer Protocol (FTP) is a type of TCP, which is specifically used to transfer files between computers and uses the Port 20 or 21.
The hardware and software needed to connect two disparate network environments.
Graphical User Interface interfaces the PC to any external device. Hot areas on the computer screen can be programmed to activate a function or activity in the device.
A magnetic medium for storing digital information on most computers and electronic equipment that process digital signal.
A base 16 numbering system using ten digits and 6 letters -0,1,2,3,4,5,6,7,8,9,A, B, C, D, E, F.
Hyper Text Markup Language is a set of codes to format text and graphics that will be displayed in a browser. The code defines how the data will be displayed.
Hyper Text Transfer Protocol: The protocol used for communication between a Web server and Web browser which usually uses the port 80.
A network device that serves as a central connection point for several devices. A hub repeats the signal it receives on one port to all other ports.
Institute of Electric and Electronics Engineers Inc. is an international organisation that sets standards for various electrical and electronic issues.
Impedance is the input and output characteristic of any electrical system and is measured in ohms. For maximum signal transfer, the input and output impedance should be the same.
This is part of the TCP/IP protocol suite and is responsible for network addressing and routing.
Iris is a diaphragm which is inbuilt in a lens that can be adjusted either manually or automatically to vary the amount of light passing through the lens and falling on the CCD chip.
Integrated Services Digital Network is a telecommunication standard that is used to digitally send voice, data, and video signals over the same lines.
Internet Service Provider is a company that provides direct access to the Internet for home or business users.
A programming language developed by Sun Microsystems which can run on any platform which has a Java Virtual Machine installed.
Joint Photographic Expert Group is an ISO standard for still or single frame compression.
Layer 2 Tunnelling Protocol is a non-proprietary protocol created by the Internet Task Force for encrypting IP packets for transmission through the Internet. The host and destination routers must have the L2TP protocol installed to create a Virtual Private Network.
Local Area Network is a small network usually restricted to single or close by buildings.
Light amplification by stimulated emission of radiation. A laser produces a very strong and coherent light of a single frequency.
This is the measurement of resolution for an analogue video signal. The higher the bandwidth of the signal, the higher the number of picture lines.
A version of Unix developed by Linus Torvalds. Runs on Intel based PCs and is generally free.
Luminance is the part of the video signal containing information about the brightness of the picture
Media Access Control is a part of the network interface card (NIC) that controls the way multiple devices use the same media channel.
Mega (106) bits per sec. This is an indication of data rate
Moving Picture Expert Group is an ISO standard for moving image compression.
An MPEG standard for compressing scanned images with audio. Bit rate is from 1.5Mbps to 3.5 Mbps.
A popular MPEG standard for interlaced video signal with high quality audio with a scalable bit rate from 1.5 Mbps to 100 Mbps. Accepted as a HDTV and DVD standard
Network Interface Card connects any network device to the transmission medium.
This is an unwanted signal generated by electronic components. The noise in a video signal causes a grainy or snowy effect on the image.
National Television System Committee is a colour television system and the standard used in the USA and Japan. NTSC has 525 horizontal scanning lines and 60 fields per sec.
Ohms is a unit for measuring resistance or impedance of any electrical device
This is a software programme installed in a microprocessor-based device that controls the functionality of the device.
A unit of data sent over a network and including a header with addressing information and the data itself.
Phase Alternating Line is a colour television system and the Standard used in Western Europe, Australia, parts of Africa and Asia. PAL has 625 horizontal scanning lines and 50 fields per sec.
A TCP/IP utility used to test whether another host is reachable.
Picture element or cell, is the basic unit of a digital image.
Post Office Protocol is used to download email from a SMTP email server.
Plain Old Telephone System is an acronym for Public Switched Telephone Network (PSTN), the traditional analogue telephone network.
A pre-defined set of rules that dictate how computers or devices communicate and exchange data on the network.
A camera with a Pan Tilt head and Zoom lens.
Frequencies that are used in the wireless transmission of data, audio and video signals.
Redundant Array of Independent Disks is a configuration of multiple hard disks which provide fault tolerance i ncase one of them failS.
Random Access Memory. Electronic chips known as memory that can store digital information when power is applied to it. Capacity is measured in kilobytes (KB).
Resolution is a measure of picture definition and clarity and is represented by the number of pixels. Higher number of pixels = Higher resolution.
A connection mechanism that allows up to eight wires (or four pairs) to be connected to the network.
Connects two networks and allows packets to be transmitted and received between them. A router determines the best path for data packets from source to destination.
It is a communication protocol used for communication between microprocessor-based devices.
A process where the output changes up or down depending upon the input level.
A powerful computer that provides resources to the clients on the network.
The ratio between the signal voltage and the noise voltage generated by an electronic circuit. It is measured in decibels (db)
Society of Motion Picture and Television Engineers
SMTP stands for Simple Mail Transfer Protocol. This is the protocol used to send emails. The email first goes to the SMTP server in the host network and from there it goes to the SMTP server in the destination network.
Simple Network Management Protocol (SNMP) is the management protocol created for sending information about the health of the network to network management devices.
The device is given a fixed and permanent IP address. This address must be obtained from the network administrator or ISP.
A group of selected bits that identify a sub network within a TCP/IP protocol.
A digital connection leased from the telephone company. The bandwidth of this connection is 1.544 Mbps
A digital connection leased from the telephone company. The bandwidth of this connection is 44.736 Mbps
Transmission Control Protocol /Internet Protocol was developed by the Department of Defence as an internetworking protocol that breaks data packets into segments, numbering and send them in random order. The receiving device reassembles the data. It is the de facto standard for communication on the Internet.
The physical and logical layout of the devices in a network.
A device that transmits and receives network signals.
Twisted pair is a type of balanced cable in which a pair of cables is twisted and the signal is divided between them.
UDP stands for User Datagram Protocol. This is similar to TCP, except that in UDP there is no acknowledgment that the packet has been received at the destination. This is known as 'connection less'.
The card in a PC or any other device which grabs each frame of a moving image then digitises it and even compresses it if required.
Video motion detection
Video Motion Detection (VMD) is a device that can detect unwanted movement in the picture and then generate an alarm.
Virtual Private Networks can be set up on the Internet by encrypting the packets at the host server and than sending it to the destination server, where it is decoded. This allows secure communication between two locations.
Wide Area Network is a network that crosses local, regional and international boundaries.
A new standard for still or single frame compression that uses the frequency domain.
A computer program that uses the Hypertext Transfer Protocol (http) and is used on a workstation to communicate with other devices on the Web.
Zoom Ratio is the ratio between the maximum and minimum focal length of a zoom lens.