Show that the FIFO-ordered multicast algorithm does not work for overlapping groups, by
considering two messages sent from the same source to two overlapping groups, and considering
a process in the intersection of those groups. Adapt the protocol to work for this case. Hint:
processes should include with their messages the latest sequence numbers of messages sent to all
groups.
What will be an ideal response?
Let p send a message m1 with group-specific sequence number 1 to group g1 and a message m2 with group
specific sequence number 1 to group g2. (The sequence numbers are independent, hence it is possible for two
messages to have the same sequence number.) Now consider process q in the intersection of g1 and g2. How
is q to order m1 and m2? It has no information to determine which should be delivered first.
The solution is for the sender p to include with its message the latest sequence numbers for each group that it
sends to. Thus if p sent m1 before m2, m1 would include
had missed a message if it received m2 first.
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Pie charts are used to show how different categories relate to the ________
Fill in the blank(s) with correct word
Corrective maintenance _____.
A. adds enhancements to an operational system and makes the system easier to use B. diagnoses and corrects errors in an operational system C. involves changing an operational system to make it more efficient, reliable, or maintainable D. competes for resources in an operational system
A function that searches through a range for a specific value and returns the relative position of that value within the range.
What will be an ideal response?
Assume that a new node is introduced and is then connected to k existing nodes in the net- work. If k >> 1, how will the scaling exponent of the evolving network behave? Support your observations with simulation.
What will be an ideal response?