Homework 12

22C:116, Fall 2000

Due Friday Nov 17, 2000, in class

Douglas W. Jones

  1. At what level in the ISO OSI hierarchy is an atomic transaction protocol. Justify your answer!

  2. Problem inspired by questions 7 and 8 on page 548 of the text:

    Assume a system with a file server and a large number of compute-servers, each with a local disk, where users may freely launch applications on any compute server; the CS department network follows something close to this model!

    What files should be stored locally and what files should be stored centrally on the file server?

    b) Consider the possibility of using the local disk on each machine as a cache, storing copies of files from the central server. What criteria would you use to determine what files may be cached and what files must not be cached. Does your caching solution provide most of the solution to the problem in question 7 on page 548?

  3. Why aren't we interested in optimal load balancing algorithms?

  4. Given an operating system where all messages are addressed to processes, describe how you would construct a layer on top of the system that offers DEMOS-like message addressing.