Q2: An upper level information is divided into 10 frames, and the probability of reaching the destination without damage is 80%. If the data link protocol does not perform error control, how many times does this information need to be sent on average to reach the receiver completely?
Answers
Answer:
Explanation:
Greater than 15 seconds: rules out conversational interaction
Greater than 4 seconds: generally too long for a conversation requiring the operator to retain information in operator's short-term memory.
2 to 4 seconds: delay longer than 2 seconds can be inhibiting to terminal operations demanding a high level of concentration
Less than 2 seconds: the more detailed the information remembered, the greater the need for responses of less than 2 seconds.
Sub-second response time: certain types of thought-intensive work, especially with graphics applications, require very short response times to maintain the user's interest and attention for long periods of time.
Decisecond response time: response to pressing a key and seeing the character displayed on the screen or clicking a screen object with a mouse needs to be almost instantaneous