3.4) Other Information 3.4) Other Information ProcessesProcesses

Collecting•Different devices can be used for collecting communication data including:

• ATM terminals for banking

• EFTPOS terminals in stores

• telephones for voice mail

• keyboards for email/IM/SMS

• video cameras & microphones for teleconferencing

• smart phones for file access

Processing•After data is collected it must be converted into a suitable form for transmission.

•This processing involves encoding and decoding.

•Encoding involves converting data from its original form into some other form.

•Decoding is the reverse process.

•It converts data back from the form used for transmission back into its original form.

• A telephone encodes the sound waves of your voice into electrical signals for transmission and then they are decoded back into sound waves at the other end.

• Analog data is continuously variable and represented in waves.

• Digital data is represented in a series of jumps, or steps.

• Digital signals in information systems are represented as a series of 1’s and 0’s.

• There are four possible encoding and decoding possibilities in transmission.

• They are:

• analog to analog (e.g. telephone)

• digital to digital (transmission across a LAN)

• analog to digital – real world data encoded for computers (scanners, recording sounds to computer, digital cameras)

• digital to analog (modem converting computer data to telephone signals)

• When a modem converts a digital signal to an audible signal this is called modulation.

• At the other end this audio signal is converted back to a digital signal; this is known as demodulation.

• Attachments for emails also need to be encoded.

• Many email programs use the Multipurpose Internet Mail Extension (MIME) to transmit attachments.

• Client-server architecture describes the software relationship between the client and the server.

• A client sends a request and the server responds.

• E.g. an online newspaper delivering content to be read offline.

• Client-server architecture provides a convenient way of connecting programs that are distributed across a network.

Displaying•Text, audio and images can all be displayed through various devices.

•These include, but are not limited to:

• telephone

• EFTPOS terminal

• monitors

• data projectors