This homework assignment has five questions; answer all of them. This
assignment is due no later than 7:00 p.m. on Thursday, 1 November.
If you mail in your assignment, please submit a printable document
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Assuming a framing protocol that uses bit stuffing, show the bit sequence
transmitted over the link when the frame contains the following bit sequences
110101111101011111101011111110
Mark the stuffed bits. Justify your answer, clearly stating your
assumptions.
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Show that two-dimensional parity provides the receiver enough information to
correct any 1-bit error (assuming the receiver knows only 1 bit is bad), but
not any 2-bit error.
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The sliding-window protocol can implement flow control by having the receiver
delay ACKs, that is, by not sending ACKs until there is space in the
receiver's buffer for more payload. Explain how to implement this version of
the sliding-window protocol. Your implementation should be no less efficient
than the usual way of implementing the sliding-window protocol; justify this
property of your implementation. Characterize the circumstances in which you
would expect your implementation to be more efficient than the usual way of
implementing the sliding-window protocol.
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A is connected to B via a router R. The A-R link is
instantaneous, but the R-B link transmits only one packet each
second. Assume A sends to B using the sliding window protocol with
a sender window size of 3. For time = 0 through 4, state what packets arrive
at and are sent from A and B. How large does the queue at R
grow?
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Suppose the end-to-end propagation delay for an Ethernet is 23.2 usec. In
this circumstance, the minimum packet size on the network is 512 bits.
What happens to the minimum packet size if the delay time is held constant,
and the signaling rate rises to 100 MBps?
What are the drawbacks of the 100 MBps minimum packet size?
This page last modified on 2012 October 23.