Description
Question 1: The only things guaranteed in life are FIFO channels [20 points]
Consider a system with pair-wise FIFO communication channels. Explain, which of the ordering
properties FIFO, causal, and/or total ordering will be satisfied in the following four scenarios. For
each ordering property, either explain (in one or two sentences) why it will be satisfied, or provide a
counter-example, for example, using a diagram. The same counter-example can be used for
different scenarios. For B-multicast over FIFO channels, explain whether and why it automatically
satisfies causal ordering, or provide a counterexample.
(a) B-multicast in a situation where there are no process failures;
(b) R-multicast in a situation where there are no process failures;
(c) R-multicast in a situation where process failures may occur;
(d) The sequence number-based FIFO multicast algorithm discussed in class.
Questions 2-4 are on the next pages
