In a byte-oriented link layer protocol, the receiver adds all the bytes between the start and end marker bytes (not including those markers) modulo 239, and expects to get a result of 0 if there have been no errors. The byte immediately before the end marker is a checksum, chosen at the transmitter to make this possible. The probability of an error in any received bit is 0.00075 . The total length of the frame is 205 bytes (including start and end markers). Estimate the probability of errors occurring in the received frame but not being detected. You need to consider what combinations of bit errors could cause the error detection system to fail (i.e, conclude that there are no errors). As you are asked for an estimate, you need only consider the most likely scenarios - it is safe to ignore events that could only occur with much lower probability. Round your answer to three significant figures. As the probability will be very low in some cases, you may have to enter up to 7 digits after the decimal point, for example, 0.0000234 . A tolerance of 3% of the correct answer is allowed.

In a byte-oriented link layer protocol, the receiver adds all the bytes between the start and end marker bytes (not including those markers) modulo 239, and expects to get a result of 0 if there have been no errors. The byte immediately before the end marker is a checksum, chosen at the transmitter to make this possible. The probability of an error in any received bit is 0.00075 . The total length of the frame is 205 bytes (including start and end markers). Estimate the probability of errors occurring in the received frame but not being detected. You need to consider what combinations of bit errors could cause the error detection system to fail (i.e, conclude that there are no errors). As you are asked for an estimate, you need only consider the most likely scenarios - it is safe to ignore events that could only occur with much lower probability. Round your answer to three significant figures. As the probability will be very low in some cases, you may have to enter up to 7 digits after the decimal point, for example, 0.0000234 . A tolerance of 3% of the correct answer is allowed.

Systems Architecture

7th Edition

ISBN:9781305080195

Author:Stephen D. Burd

Publisher:Stephen D. Burd

Chapter9: Computer Networks

Section: Chapter Questions

Problem 3VE

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