03. Transmission Modes

1. Simplex Transmission

2. Half-Duplex Transmission (HDX)

3. Full-Duplex Transmission (FDX)

What are the three dataflow transmission?

Simplex Transmission

In what dataflow transmission the data can only flow in one direction, which is usually from the source to the sink?

Half-Duplex Transmission (HDX)

In what dataflow transmission the data can flow in both directions, but never simultaneously? It first flows in one direction, then in the other direction.

Full-Duplex Transmission (FDX)

In what dataflow transmission the data can flow in both directions simultaneously?

Full-Duplex Transmission (FDX)

What can be viewed as a pair of simplex lines between the source and sink with one line going from the source to the sink and the other going from the sink to the source?

1. Serial Data Transmission

   1. Asynchronous Transmission

   2. Synchronous Transmission

2. Parallel Data Transmission

What are the two data transmission?

Serial Data Transmission

In what data transmission: when data is sent or received, the data bits are organized in a specific order since they can only be sent one after another?

Asynchronous Transmission

What is used when data is transmitted as individual characters?

Asynchronous Transmission

In this method, each character is preceded by one start bit and one or two stop bits that are used by the receiver for synchronization purposes.

Synchronous Transmission

What is used to transmit large blocks of data at a time?

Synchronous Transmission

In this scheme, data is usually organized in frames and each frame is preceded by a flag that consists of a few bits and terminated by another flag.

Parallel Data Transmission

What data transmission: multiple data bits are transmitted over multiple channels at the same time?

Transmission Media

What is the communication channel that carries the information from the sender to the receiver in which data is transmitted through the electromagnetic signals via copper wire, fiver optics, atmosphere, water, and vacuum?

Transmission Media

The function of […] is to carry the information in the form of bits through the networl.

1. Guided Media

2. Unguided Media

What are the two types of transmission media?

Guided Media

Which enables the transfer of information between two or more points that are connected by an electrical conductor?

1. Twisted Pair

2. Coaxial Cable

3. Optical Fiber

What are the examples of guided media?

Twisted Pair

Which consists two insulated copper wires that are typically about 1mm thick and twisted together in a helical form?

Coaxial Cable

In order to facilitate two-way communication, the cable bandwidth is split into two sets of channels: upstream channels and downstream channels.

Optical Fiber

Which refers to the medium and the technology associated with the transmission of information as light pulses along a glass or plastic wire?

Unguided Media

What do not physical links between two or more devices?

Wireless Communication

It is about unguided media wherein it is based on radio waves communications in the frequency spectrum.

1. Radio Waves

2. Microwave

3. Infrared

What are the examples of unguided media?

Radio Waves

Which are easy to generate and can penetrate through buildings? The sending and receiving antennas need not be aligned.

Radio Waves

What unguided media has this as examples: AM and FM radios and cordless phones?

Microwave

Which is a line of sight (LOS) transmission i.e. the sending and receiving antennas need to be properly aligned with each other?

Infrared

Which are used for very short distance communication?

Infrared

Which cannot penetrate through obstacles and prevents interference between systems?

Infrared

What is used in TV remotes, wireless mouse, keyboard, printer, etc.?

Antennas

What is the metal rod or dish that catches radio waves and turns them into electrical signals feeding into something like a radio or television or a telephone system?

1. Log Periodic Antennas

2. Wire Antennas

3. Traveling Wave Antennas

4. Microwave Antennas

What are the example types of antennas?

Log Periodic Antennas

What is the directional antenna that is made of a series of dipoles placed along its axis at different space intervals of time followed by a logarithmic function of frequency?

Wire Antennas

What antennas use a length of wire for transmitting and receiving wavelengths of signals?

Traveling Wave Antennas

What is the directional aperiodic antenna that uses a travelling wave as its guiding structure?

Traveling Wave

What is the temporary wave that creates a disturbance and moves along the transmission line at a constant speed?

Microwave Antennas

Which antenna uses microwave transmission to broadcast signals between two or more locations?

Microwave

What is the form of electromagnetic radiation that is used mostly in point-to- point communications and radar?

Frequency Spectrum

What is the range of frequencies contained by a signal?

What are the following frequencies that are designated by the International Telecommunications Union (ITU)?

Wave Propagation

What is basically defined as superimposed oscillations of an electric and a magnetic field in space with their direction of propagation perpendicular to both?

1. Ground Wave

2. Sky Wave

3. Space Wave

What are the following propagation that is currently used today?

Ground Wave

What is used for a low-frequency range transmission, mostly less than 1 MHz?

Ground Wave

What type of propagation is this that use of large antennas order of which is equivalent to the wavelength of the waves and uses the ground or Troposphere for its propagation?

Sky Wave

What is used for the propagation of EM waves with a frequency range of 3-30 Mhz?

Sky Wave

Which waves makes the use of ionosphere in which it is the ionized part of the earth’s upper atmosphere?

Space Wave

What is used for a line of Sight communication (LoS)?

Space Wave

Space satellite communication and very high-frequency waves use this propagation method.

Multiplexing

What is the way of sending multiple signals or streams of information over a communications link at the same time in the form of a single, complex signal?

Demultiplexing

In multiplexing, the receiver recovers the separate signals, a process called […].

Media Sharing Technique

This is the

1. Frequency-Division Multiplexing (FDM)

2. Time-Division Multiplexing (TDM)

3. Spread Spectrum (SS)

What are the three examples of media sharing technique?

Frequency-Division Multiplexing (FDM)

What media sharing technique is it where the frequency spectrum of the medium is partitioned into multiple frequency blocks called channels that are assigned to users who can use these channels simultaneously without interference from each other?

Time-Division Multiplexing (TDM)

What media sharing technique is it where transmission time is divided into non-overlapping time slots that are assigned to users?

Time-Division Multiplexing (TDM)

Transmissions are staggered using a round-robin method to schedule the transmissions.

Spread Spectrum (SS)

What media sharing technique is it where the output signal, which appears like noise, occupies more bandwidth than the original signal?

1. Carrier Sense Multiple Access with Collision Detection (CSMA/CD)

2. Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA)

3. Token Passing

4. Demand Priority

What are the examples of Media Access Methods?

1. Carrier Sense

2. Multiple Access

3. Collision Detection

What are the three examples of Carrier Sense Multiple Access with Collision Detection (CSMA/CD)?

Carrier Sense

Which means that each station on the LAN continually listens to (tests) the cable for the presence of a signal before transmitting?

Multiple Access

Which means that many computers are attempting to transmit and compete for the opportunity to send data (i.e., they are in contention)?

Collision Detection

Which means that when a collision is detected, the stations will stop transmitting and wait a random length of time before retransmitting the data?

Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA)

Instead of detecting and reacting to collisions, […] tries to avoid them by having each computer signal its intention to transmit before transmitting.

Token Passing

What is the media access method by which collisions are prevented?

Token Passing

Collisions are eliminated under […] because only a computer that possesses a free token (a small data frame) can transmit.

Token Passing

This method also allows different priorities to be assigned to different stations on the ring.

Demand Priority

In […], an active hub is an essential requirement that can control access to the network.

Demand Priority

The terminals on a network are required to obtain permission from the hub before they start transmitting the bytes over a network.