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Implement a small software that computes the CRC-32 for a text file. Then, modify the contents of the file to change an even number of bits or an odd number of bits inside the file. When modifying the file, remember that an ASCII file is composed of 8 bits characters that are encoded by using the ASCII table that you can find at : http://en.wikipedia.org/wiki/ASCII . You can also write a small program that produces binary files that are a small variation of each other.
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hundred frames
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How would you set the duration of the retransmission timer in the alternating bit protocol ?
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Each frame contains `D` bytes of data and `c` bytes of control information
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Each acknowledgment contains `c` bytes of control information
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Discussion questions
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Derive a mathematical expression that provides the `goodput`, i.e. the amount of payload bytes that have been transmitted during a period of time, achieved by the Alternating Bit Protocol assuming that :
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Consider two high-end servers connected back-to-back by using a 10 Gbps interface. If the delay between the two servers is one millisecond, what is the throughput that can be achieved by a reliable protocol that is using 10,000 bits frames and a window of
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A version of the Alternating Bit Protocol supporting variable length frames uses a header that contains the following fields :
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a `number` (0 or 1)
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all errors that affect a sequence of bits which is shorter than the length of the CRC
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all errors that affect an odd number of bits
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a `length` field that indicates the length of the data
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a Cyclic Redundancy Check (`CRC`)
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