CS 417 Exam 1

Fall 2007

    Part I – 30 Points

  1. 5 points
    What problem was a snoopy cache designed to solve (compared to a regular processor cache)?
  2. 5 points
    Your network requires the ability to address 500 hosts. A class B network, with a 16-bit host address, has the ability to address 65,534 hosts. 55,034 potential addresses are hence wasted. Will using CIDR instead of a class B address help? Explain how or, if not, explain why not.
  3. 5 points
    Most RPC systems require an interface definition language. Explain the purpose of an IDL.
  4. 5 points
    Explain what is meant by marshaling and unmarshaling in the context of remote procedure calls.
  5. 5 points
    Contrast the approach to caching in AFS to that in NFS.
  6. 5 points
    AFS is a stateful file system. What state does the server have to maintain?

    PART II – 70 points

    For each statement, select the most appropriate answer.

  7. A vector (or array) processor is an example of the following architecture:
    (a) Processor pool.
    (b) NUMA (non-uniform memory access).
    (c) SMP (symmetric multiprocessors).
    (d) SIMD (single instruction, multiple data).
  8. The fastest memory interconnect for a massively parallel multiprocessor system is:
    (a) system bus.
    (b) crossbar switch.
    (c) omega network.
    (d) NUMA (non-uniform memory access).
  9. Compared to a baseband network, a broadband network:
    (a) offers more bandwidth.
    (b) offers lower latency.
    (c) allows multiple data streams to be sent at the same time.
    (d) is better suited to home networking.
  10. Sending a packet on an ethernet network relies on:
    (a) waiting for the network to be free, sending the packet, and then checking for a collision.
    (b) avoiding collisions by ensuring that only one node transmits at a time.
    (c) assigning specific time slots during which each node is allowed to transmit.
    (d) assigning each node a unique frequency for transmitting data.
  11. Which layer of the OSI reference model do TCP and UDP occupy?
    (a) UDP: network layer (3); TCP: transport layer (4).
    (b) UDP: transport layer (4); TCP: transport layer (4).
    (c) UDP: network layer (3); TCP: network layer (3).
    (d) UDP: transport layer (4); TCP: network layer (3).
  12. ARP, the Address Resolution Protocol:
    (a) resolves conflicts if two devices have the same IP address.
    (b) resolves conflicts if two devices have the same ethernet address.
    (c) finds the IP address for a given ethernet address.
    (d) finds the ethernet address for a given IP address.
  13. UDP:
    (a) ensures that packets arrive in the same order they were transmitted.
    (b) retransmits lost packets.
    (c) drops packets with corrupt data.
    (d) none of the above.
  14. Which sequence of system calls establishes a connection-oriented socket, names it, sets it for receiving connections, and waits for an incoming connection?
    (a) connect, bind, listen, accept.
    (b) socket, bind, recv, accept.
    (c) connect, biund, recv, listen.
    (d) socket, bind, listen, accept.
  15. Nagle's algorithm:
    (a) allows a programmer to set bits in an IP header to request a certain level of service.
    (b) groups related flows of IP packets together at the router.
    (c) avoids sending lots of small TCP packets.
    (d) retransmits IP packets at increasing intervals to relieve network congestion.
  16. ATM is most accurately described as a network that:
    (a) employs hard QoS to switch a stream of variable-size packets.
    (b) employs hard QoS to switch a stream of fixed-size packets.
    (c) employs soft QoS to switch a stream of variable-size packets.
    (d) employs soft QoS to switch a stream of fixed-size packets.
  17. DCE RPC improved on SUN (ONC) RPC by adding:
    (a) an interface definition language.
    (b) a cell directory server.
    (c) an interface pointer to support objects.
    (d) dynamic selection of TCP or UDP.
  18. Which of the following best describes the distinction between a name and an address?
    (a) A name is human-friendly; an address is machine-friendly.
    (b) An address is unique; a name does not have to be unique.
    (c) An address is a location associated with the name.
    (d) A name is alphanumeric; an address is numeric.
  19. Which is the least accurate statement about SOAP?
    (a) SOAP is a highly-compact way of representing procedure calls.
    (b) SOAP passes through content-inspecting firewalls by using HTTP.
    (c) SOAP uses explicit typing in an XML structure.
    (d) SOAP integrates with Microsoft .NET remoting.
  20. Compared with sequential semantics, session semantics:
    (a) usually require more network messages.
    (b) make file locking impossible.
    (c) make concurrent modifications impossible.
    (d) make it difficult to do client-side caching.