3.1.7

Question 1

What are protocols?

Answer 1

• Protocols are the set of rules computers follow
  when communicating across a network.
• Without them, no information can be transmitted
  as computers don’t know how to interpret the
  signals coming through the network.

Question 2

Functions of a protocol

Answer 2

• Ensure data integrity
• Manage flow control
• Prevent deadlock
• Manage congestion
• Perform error checking

Question 3

What is data integrity?

Answer 3

Data integrity refers to the overall completeness, accuracy and consistency of data.

Question 4

What is flow control?

Answer 4

• Flow control is the mechanism that ensures the rate at which a sender is transmitting is in proportion with the receiver’s receiving capabilities.
• Flow control is utilized especially in cases where the sending device can send data much faster than the receiver can digest.

Question 5

What is deadlock in networking?

Answer 5

Deadlock occurs when competing tasks prevent each other from completing, leading to a system being stuck in an endless loop.
Example: Multiple processes on a PC try to “swap” to virtual memory, causing “thrashing” and system instability.

Question 6

What is congestion in networking?

Answer 6

Congestion refers to significant slowdowns in communication due to overburdened communication channels (e.g., wires, routers).
Unlike deadlock, congestion does not halt processes but leads to inefficiency and slower data transfer.

Question 7

What is error checking?

Answer 7

• Error checking or detection refers to the techniques used to detect noise or other impairments introduced into data while it is transmitted from source to destination.
• Error detection often makes use of parity bits, bits at the end of a packet that are calculated to be either a 1 or 0.

Question 8

A website allows members to place orders for products. A person may become a member by completing an online form with their details, including payment method, email address and password. To order from the site a member must enter a username and a password.
Explain the role of protocols when a member access the site

Answer 8

Protocols like HTTPS and TLS play a crucial role when a member accesses the website by ensuring secure communication between the user’s device and the server. HTTPS, using TLS encryption, protects sensitive data such as usernames, passwords, and payment details from interception or tampering during transmission. These protocols also authenticate the website’s identity, ensuring the user is interacting with a legitimate site, thereby enhancing security, data integrity, and user trust.

Question 9

Outline the importance of network protocols

Answer 9

1. Ensure data integrity
2. Prevent deadlock