Network Management Midterm Study Guide   

Here are the OpenFlow sections from An Introduction to Computer Networks that you should be familiar with:

Also the following, with the understanding that Python won't be on the exam:

Here are the SNMP sections that may be covered, from the SNMP chapter:

Here's a summary of important SNMP-Table topics without reference to sections from the book:
You will be given copies of the mib-2 system and interfaces group definitions from this slightly edited version of the RFC1213 MIB. (Actually, because this exam is online, I will most likely include a link to the full MIB as well).
The midterm covers up through SNMP version 2.

Answers are now here.
(For some of these examples, you may need to look at the answer to figure out what I'm talking about And remember that you will have some MIB file (probably part of RFC1213) to use as a syntax reference.)

For OpenFlow, see these exercises at


1. Suppose we want to create a new snmp table, called carTable. The prefix is vehicles::= The carTable is to consist of sets of entries of form
    make (gm, chrysler, ford, nissan, toyota)
The index is to be a field carNum.
Give an ASN.1 definition for carTable, carEntry, and the entry fields. Model it after ifTable.

(This is a general problem on how to define tables)
2. What is the problem with conventional switches and a loop topology, and how are OpenFlow/SDN switches able to accommodate this?

    |       |
3. What is the simplest way, using SNMP, to
  (a) retrieve a single row of a table (say row 3, where the columns are T.1 through T.7)
  (b) retrieve a single column of a table (say column 5, with pseudo-header T.5, and 6 rows)
5. In the IP group, mib2.4, part of RFC1213-MIB, there are several tables:
The following apply to the last table.
(a). List the columns under ipNetToMediaEntry.
(b). Draw a table representing these entries. Create at least two rows. Make up plausible values.  

7. Suppose you are on a subnet. One workstation on the subnet is also a router to the outside world. What SNMP tables might help you to determine which workstation is the router?

What if the workstation were a switch and not a router?
8. Account for the differences between TCP and UDP in the RFC1213-MIB (mib-2). That is, explain the differences and explain why they are there.
9. Consider a simplified version of the RFC1213-MIB Interfaces table (some columns described in M&S, p 349), with entries for ifIndex, ifDescr, and ifSpeed.
(a). Give the OIDs for the columns themselves.
(b). Suppose the table has the following data: 

Give the full OIDs for each of these six table entries.

You may express the OIDs as either or as mib-2.________
10. Consider the ETHERLIKE-MIB for ethernet-like nodes, and
(a) identify how to find the number of collisions
(b) identify how to determine if any host is violating the 1500-byte maximum packet size
(c) identify how to determine the rate of collisions per good packet.

11. Be familiar with get-next traversal, and at least somewhat familiar with the get-bulk extension. In what order will values be retrieved from the following table?

                      |         |
                      |    T    |
                      |         |
                      |         |
                      |    E    |
                      |         |
         |                 |                 |
    +---------+       +---------+       +---------+
    |         |       |         |       |         |
    | T.E.1.1 |       | T.E.2.1 |       | T.E.3.1 |
    |         |       |         |       |         |
    +---------+       +---------+       +---------+
         |                 |                 |
    +---------+       +---------+       +---------+
    |         |       |         |       |         |
    | T.E.1.2 |       | T.E.2.2 |       | T.E.3.2 |
    |         |       |         |       |         |
    +---------+       +---------+       +---------+
         |                 |                 |
    +---------+       +---------+       +---------+
    |         |       |         |       |         |
    | T.E.1.4 |       | T.E.2.4 |       | T.E.3.4 |
    |         |       |         |       |         |
    +---------+       +---------+       +---------+

12. Consider the network below, in which switches s1-s4 each have port numbers 1, 2 and sometimes 3 as shown

  h1          h2          h3          h4
  |           |           |           |

  1           1           1           1

Give flow-table entries for S1-S4 (or just S1 and S2) that match any traffic between the hosts using the l2_pairs approach. For example, s1 will include the following rules:
(this is all for s1, because any traffic not involving h1 will not pass through s1.)

13. Do the same as in 12 above, except give the forwarding entries if the l2_nx approach (two tables, T0 and T1) are used. Assume T0 is used to match destination addresses and T1 is used to match source addresses. The default rules for each table are as follows:

T0: match nothing: flood, send to T1
T1: match nothing: send to controller