CPSC 441, Fall 2004
Information about the Third Test

The third test in this course will be given during the scheduled final examination period for this course, on Wednesday morning, December 15. However, we have decided that the exam will begin at 10:00 AM, instead of at the scheduled 8:30 AM. The paper for your final project (if you are doing one) can be turned in at the exam or during my office hours later on Wednesday.

The exam will be four pages long. One page will be a 25-to-30 point essay question that will ask you to discuss the general idea of layered network protocols and also the five specific protocol layers that are used in the Internet. The other three pages will concentrate on material that we have covered since the second test. Although there might be a few questions on the most important ideas from earlier in the course, you will not be asked for details about, for example, the HTTP protocol, the TCP congestion control algorithm, or the contents of the IP packet header.

One of the topics for the test is MPI. You will not have to memorize the parameters of each MPI functions. If there are any questions that require you to use these functions, a parameter specification will be provided. The other new topic for this exam is Chapter 5 from the textbook, covering the Link Layer. The reading from this chapter was Sections 5.1, 5.3, 5.4, 5.5, and 5.6, although we did not cover all the topics in these sections. The labs covered on this test are labs 9, 10, and 11.

My office hours for next week include:

         Monday, December 13:    11:00 -- 12:00
         Tuesday, December 14:   11:00 -- 3:00 
         Wednesday, December 15: 12:00 -- 4:00

Following are some terms and ideas that you should be familiar with from the new material. This is in addition to the most important material from Test 1 and Test 2.


   The link layer                                 Parallel and distributed processing
   Frames                                         Shared memory parallel processing
   NIC (Network Interface Card)                   Distributed memory processing
   Shared medium vs. point-to-point               Message passing
   Multiple access protocol                       Network topologies
   Approaches to multiple access:                    static (such as ring, mesh, hypercube)
      channel partitioning (TDM, FDM, CDMA)          switched (such as switched Ethernet)
      taking turns (token ring)                   Beowulf
      random access (Ethernet, wireless)             console/master node 
   CSMA (Carrier Sense Multiple Access)              dedicated compute nodes 
   CSMA/CD (CSMA with Collision Detection)           nodes connected by a private network
      -- used in Ethernet                         Network of workstations

   Ethernet                                       MPI (Message-Passing Interface)
      collision domain                            MPI virtual machine
      Ethernet's response to a collision          Process_count in MPI
      exponential backoff                         Rank of a process
      format of Ethernet addresses                MPI messages
      assignment of Ethernet addresses            MPI_Send
      Ethernet frame                              MPI_Recv
      CRC (Cyclic Redundancy Check)               Collective communication
                                                  MPI_Reduce
   Hubs                                           MPI_Scatter
   Link-layer switches                            MPI_Gather
   Collision domains in hubs vs. in switches      Communication overhead
   MAC address                                    Load balancing
   ARP (Address Resolution Protocol)              Master/slave design
   ARP requests and responses                     Embarrassingly parallel problems