Discussion Questions

Questions to discuss for the VL2 paper. Discuss any one of the issues listed below. Please post your response at http://hydralisk.cs.washington.edu.

  1. One of VL2's design goals is to support agility. Justify or critique this design goal in building datacenters. Would you rank other goals to be more important than this one?
  2. VL2 provides full-bisection bandwidth (i.e., the network is not oversubscribed even at the top levels of the datacenter switching topology). Justify or critique this design choice.
  3. The paper presents a set of results from the analysis of datacenter traffic patterns. What did you find interesting about these traffic patterns? What are the implications of these traffic patterns? These traffic patterns are gathered from a particular datacenter cluster. Do you think they generalize to other datacenters? If not, why?
  4. What did you find interesting about VL2's routing mechanisms? How does it compare to routing in a traditional switched ethernet or routing within an AS?
  5. VL2 uses a directory server. What should be the design goals of this directory server? Do you think VL2's design decisions with respect to the directory server are good/reasonable?