CS2680 6-1-clos

Reading Review for Class 9

This class’s readings are:

• Fat-Tree (Sections 1-3)
• Jupiter Rising (Sections 1-4, 6)

Your review should include both a summary of these papers, which discusses

• the problem the paper addresses
• the paper’s solution
• the evidence the paper provides that the solution was correct. Remember to keep in mind the historical context the papers discuss.

Your review should also discuss, after the summary:

• whether the problem the paper solved is an important one
• whether the solution was a good one
• whether the paper was fun or enjoyable to read.
• what questions you have about the paper, or which parts of the paper (if any) you found hard to understand.

You should answer the above questions in about one sentence each. The remainder of your review (about the below questions) should be about a page (~500 words) long.

Finally, for this week’s papers, please reflect on the following questions:

• Figure 3 in the Fat-Tree paper shows an example of a fat-tree topology. However, Figure 3 doesn’t show how this network could be connected to the outside world. Describe a modification to the network shown in Figure 3 that would enable external connectivity (note that the Jupiter Rising paper discusses this).
• Both papers describe over-subscription of the network core. What application or workload patterns does over-subscription assume? What application patterns would over-subscription be ill-suited for? How much (approximately) resources does over-subscription save?