Communications

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** Communication Systems ** enable people and systems to share and exchange data and information electronically.

**VoIP:​ ** Voice over Internet Protocol transfers voice calls over the public internet. VoIP is also known as IP Telephony, Voice over broadband and Internet Telephony. The main things to know about VoIP are:
 * It is possible to transfer voice over the internet using any internet connection combined with a microphone, speakers and one of the many free instant messaging applications, such as MS Messenger, for example.
 * Calls are significantly cheaper as the public internet carries the data for free regardless of distance.
 * There is no added cabling required to add extra VoIP lines.
 * Additional digital services, such as voice mail, conference calls and video calls are much simpler to add as the data is digital.
 * VoIP calls can originate from any location with an internet connection.

**Video: What is VoIP? ** media type="file" key="What is VoIP.flv" width="360" height="270"

**__Video on Demand:__** Video on Demand enables users to select videos from a central server for viewing on a television or computer screen. This type of emerging technology has the ability to deliver a movie or other video program to an individual web browser or TV set whenever the user requests it.

Video on Demand is used for: - Entertainment - Education - Video Conferencing

The aim of all VOD systems is to provide users with high quality video immediately in real time. Current, 2007 transmission speeds and compression technologies are insufficient for this aim to be achieved. Online VOD websites deliver a wide range of movies, although these movies must be downloaded prior to viewing which may take very long.

Click on the image below to view an example of a website offering Video on Demand: The website above, allows users to sign up by applying for an account, and at the users request to search for videos, which would could be purchased. When purchased it allows you to keep the video for the time set. This website also allows you to view videos online and they have plans which may be chosen by the user. Source - [] To have this information read out, press on the play button on the right: media type="file" key="video on demand.m4a" width="300" height="50"

<span style="font-family: Arial,Helvetica,sans-serif; font-size: 12pt;">__**3G Networks:**__ Third generation (3G) networks currently provide wireless connections that transmit and receive voice, video and data to mobile handsets. 3G networks were first introduced nationally in Japan in 1999. 3G networks allow you to stay in contact in more ways than available on a normal mobile phones. With 3G capable mobiles giving you constant access to the internet and emails, it becomes a breeze to keep a company organised, even when people are on the road. 3 major companies which support 3G networks are Optus, Telstra and Vodafone. They are all investing in the upgrade of third generation networks, which should give the paying public faster downloads and better services.

For more information:
 * go to the page named Related Links in tool Bar (on the right hand side):or click here
 * or click on the pdf file below





<span style="font-family: Arial,Helvetica,sans-serif; font-size: 12pt;">__**Bluetooth:**__ Bluetooth is a communication system for short-range transmission. The aim of Bluetooth was to replace cable connections for portable devices. Bluetooth devices are programmed to detect Bluetooth items automatically, and also form a network known as a piconet (each device is able to connect to multiple ‘piconets’ at a time. For example; A Bluetooth headset is able to form a piconet network with a mobile phone as the mobile phone establishes one with a laptop over another piconet. Nodes that are connected to a piconet, share one single communication channel. This channel splits into time slots that evenly spaced and data packets are placed in these slots during transmission. In Bluetooth transmission, one device is declared the master while others are the ‘slaves’- slaves are only able to communicate with the master. //<span style="font-family: Arial,Helvetica,sans-serif; font-size: 12pt;">The Master: // is the controller is able to control and manage the network. The master alters the frequency used by the controls used at regular intervals (this is set up by the system clock. The system clock also synchronises the transmission of packets between nodes. They use of a single clock makes it possible for Bluetooth devices to work over short distances). This is done to avoid interference with other devices and piconets that may be operating in that range or close by. The actual distance that a device can stretch is determined by the strength of the transmitter that is in each device. For instance, those with lower connection power must be less than one meter away, and those with a higher power can stretch to up to 100 meters. Generally, Bluetooth transmits data and approximately 1 Mps, however with the use of the EDR (Enhanced Data Rate) mode it is possible to achieve 3 Mps. That allows people to share information, and it can be done over vast distances (eg; from country to country) × It’s simplistic: There is no need for a complicated and detailed knowledge of how it works, mainly because it is so simple and easy to use. × <span style="font-family: Arial,Helvetica,sans-serif; font-size: 12pt;">It’s inexpensive: It’s free. So there isn’t a bill that arrives or money that you have to pay to a service provider. || <span style="font-family: Arial,Helvetica,sans-serif; font-size: 12pt;"><span style="font-family: Arial,Helvetica,sans-serif; font-size: 110%;"> × Battery Use: Enabling Bluetooth requires more energy because of the data transfer. <span style="font-family: Arial,Helvetica,sans-serif; font-size: 13.2pt;">× Bluetooth Internet: When using 'Bluetooth internet' the connection can be very slow. ||
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 110%;">**<span style="font-family: Arial,Helvetica,sans-serif; font-size: 12pt;">Advantages of Bluetooth: ** || <span style="font-family: Arial,Helvetica,sans-serif; font-size: 110%;">**<span style="font-family: Arial,Helvetica,sans-serif; font-size: 12pt;">Disadvantages of Bluetooth: ** ||
 * <span style="font-family: Arial,Helvetica,sans-serif; font-size: 110%;"><span style="font-family: Arial,Helvetica,sans-serif; font-size: 12pt;"> × Bluetooth is a widely used technology: