Computer Science 825
                           Quiz 1      Name _______________________

Terminology:  the very highest layer is the APPLICATION LAYER
              the very lowest  layer is the PHYSICAL LAYER

Suggestion:   READ the questions carefully... some with minor
              changes in terminology from old quizzes have
              DIFFERENT ANSWERS from their counterparts.

1. What is the highest layer that must be implemented in every
   IMP in a store and forward network.




2. What is the lowest layer which is normally present in hosts
   but not in IMP's.



3. At which layer is it most necessary that a common protocol
    be implemented within all nodes of a network.



4. Which two layers does the TCP / IP network architecture specify

   a. Data Link and Physical     b. Application and Transport

   c. Network and Transport      d. None of the above

5. The ISO's 7 Layer network architecture was significantly influenced by:
   an earlier network architecture. This precursor was:

   a. DECNET .. an architecture  b. The TCP/IP network architecture.
      based on ad hoc networks
      of Digital Equipment Co's
      mini computers.

   c. IBM's Systems Network      d. The MAP/TOP architecture for
      Architecture.                 Computer Integrated Mfg. (CIM)

6. Do protocols (as the term is normally used in networking, e.g
   in SDLC, TCP, or IP) define the rules under which a layer communicates

   a. With the layer above it   b. With a peer layer in another node.

   b. With the layer below it.  d. All of the above.


7. How many distinct signal states would be needed to achieve
   a transmission rate of 2^20 bits/sec while signalling at
   2^13 baud.









8. Two things that a protocol can do to earn the term "unreliable"
   are (1) deliver packets with bits that have been inverted and
   (2) lose packets.  Identify two others:

   a.


   b.


9. PROTOCOLs define 3 aspects of messages passed in a network.
   One is the SEQUENCING. What are the other two?

   a.


   b.


10. For two separate implementations of a specific network
    architecture to interoperate correctly it is necessary that:

    a. Internal interlevel interfaces  b. Intra level peer protocols
       be comptatible.                    be compatible

    c. Both a and b.                   d. Neither a. or b.


11. Place the following protocols at the correct location in the
    boxes below:  UDP, IP, ATM(datalink layer)


                   Connection        Connection
                   Oriented             Less
               ___________________________________
               |                 |               |
     Reliable  |                 |               |
               |                 |               |
               |_________________|_______________|
               |                 |               |
     Unreliable|                 |               |
               |                 |               |
               |_________________|_______________|