1. Types of Communication
A. Simplex
- Definition: Data flows in one direction only.
- Example: Like a one-way street.
- Key Features:
- Sender → Receiver
- Receiver cannot reply.
- Use Cases:
- Television broadcasts – TV station sends, viewers only receive.
- Radio broadcasting.
B. Half-Duplex
- Definition: Data flows in both directions, but one side at a time.
- Example: Like walkie-talkies (push-to-talk).
- Key Features:
- Sender ↔ Receiver, but only one speaks at a time.
- Needs a protocol to manage turns.
- Use Cases:
- Walkie-talkies.
- Older shared Ethernet networks.
C. Full-Duplex
- Definition: Data flows in both directions simultaneously.
- Example: Like a phone call – talk and listen at the same time.
- Key Features:
- Sender ↔ Receiver communicate at the same time.
- Faster and more efficient than half-duplex.
- Use Cases:
- Mobile phones.
- Modern Ethernet networks.
2. Key Comparisons
| Feature | Simplex | Half-Duplex | Full-Duplex |
|---|---|---|---|
| Data Flow | One direction | Both directions (one at a time) | Both directions (simultaneously) |
| Communication | One-way only | Two-way, but alternating | Two-way, concurrent |
| Speed | Slow | Moderate | Fast |
| Examples | TV, Radio | Walkie-Talkies | Phone calls, Ethernet |
3. Quick Recap
- Simplex: One-way only → Example: TV.
- Half-Duplex: Two-way, but one at a time → Example: Walkie-Talkie.
- Full-Duplex: Two-way, simultaneous → Example: Phone call.
MCQ
1. What is Simplex Communication?
- A) A two-way communication system.
- B) Communication that occurs in one direction only.
- C) Data flow in alternate directions but one at a time.
- D) None of the above.
Answer: B
2. An example of Simplex communication is:
- A) Telephone call.
- B) Television broadcast.
- C) Walkie-talkie.
- D) Email communication.
Answer: B
3. Which type of communication allows data to flow in both directions, but only one direction at a time?
- A) Simplex.
- B) Half-duplex.
- C) Full-duplex.
- D) None of the above.
Answer: B
4. Walkie-talkies operate in which mode of communication?
- A) Simplex.
- B) Half-duplex.
- C) Full-duplex.
- D) All of the above.
Answer: B
5. Which communication mode allows simultaneous data flow in both directions?
- A) Simplex.
- B) Half-duplex.
- C) Full-duplex.
- D) None of the above.
Answer: C
6. Which of the following is an example of Full-duplex communication?
- A) Television broadcasting.
- B) Chat applications.
- C) Walkie-talkies.
- D) Public address system.
Answer: B
7. The primary distinction between Simplex and Half-duplex modes is:
- A) Simplex allows bidirectional communication; Half-duplex does not.
- B) Half-duplex allows bidirectional communication but not simultaneously; Simplex is unidirectional.
- C) Both allow simultaneous bidirectional communication.
- D) None of the above.
Answer: B
8. A telephone call is an example of which communication mode?
- A) Simplex.
- B) Half-duplex.
- C) Full-duplex.
- D) Multiplex.
Answer: C
9. In which communication mode is the entire bandwidth dedicated to a single direction at a time?
- A) Simplex.
- B) Half-duplex.
- C) Full-duplex.
- D) None of the above.
Answer: B
10. Which of these statements about Full-duplex communication is true?
- A) Data flows only in one direction.
- B) Data can flow in both directions but not at the same time.
- C) Data can flow in both directions simultaneously.
- D) None of the above.
Answer: C