Examples of Communication Systems

Teleconferencing Systems

Teleconferencing: The use of electronic transmission to allow a meeting to occur at the same time at different locations
- Alternative to face-to-face meetings
- System that allows meetings at same time different location to occur

Audio Conferencing vs Video Conferencing

Audio Conferencing: A teleconferencing call which only uses audio
- Audio data is transmitted and received through telephone lines or via the internet.
- E.g. Phone call with 3 or more participants
Video Conferencing: A meeting which allows people in different locations to see video images of each other on a screen as well as hear speech
- Audio and video are difficult to transmit due to the large amount of data and synchronization
- MPEG-4 → ****The standard for video conferencing as compression methods lower the amount of data which needs to be transmitted whilst retaining quality
- Video conferencing uses cameras and microphones to collect data
- E.g. Zoom call

Multicasting vs Unicasting

Multicasting: Sending station transmits the signal so that a single signal is carried to all the connected stations (clients)
Unicasting: Sending station transmits the signal so that a single signal is carried to one connected station (clients)
- Signal must be sent multiple times, one by one, each time for a single client/station

Uses of teleconferencing

Distant Education: Teachers/students don’t need to pay for travel/accommodation to attend lectures
- Teleconferencing allows interactivity as it allows both parties to talk
Business Meetings: Use of teleconferencing means that meetings/conferences can be held without the need for participants to be in the same location
Job Interviews: Possible to interview a job application located at a remote location
General/Personal Teleconferencing: Even with an inexpensive webcam and internet, teleconferencing is possible
- Example: Skype is inexpensive to use and set up

Advantages vs Disadvantages

Advantages	Disadvantages
Can simulate face-to-face meeting	Lack of personal contact
Reduces costs (airfares, accommodations, meals)	Limits inter-personal relationship formed through meeting
Saves time/energy for travelling and attending	-

Messaging System: Used to send message to people in different locations who may receive the message at a different time