CREST Practitioner Security Analyst (CPSA) Practice

Which type of message is known as unicast?

1. A message sent to a group of hosts

2. A message sent from one sender to multiple recipients

3. A message sent from a single sender to a single recipient

4. A message sent to all nodes in a network

The correct answer is: A message sent from a single sender to a single recipient

Unicast refers to a communication method in networking where a message is sent from a single sender to a single recipient. This type of message is directed specifically and solely at one target host, ensuring that only that particular recipient receives the transmission, distinct from other forms of communication like multicast or broadcast. In the context of networking, unicast is often utilized for direct communication sessions, such as web browsing, where a user's request for a webpage is sent to the server, and the corresponding response is sent back uniquely to that user. The characteristic of unicast communication highlights its precision and the efficiency it provides in scenarios where targeted messaging is essential. Understanding this concept is crucial when considering the different communication methodologies in network design and security, as it helps determine appropriate approaches for managing data flow and analyzing potential vulnerabilities associated with distinct communication types.