22. Ensuring Network Availability

Question 1

1. What protocol provides detailed information on traffic flows between endpoints?
   a. Syslog
   b. SNMP
   c. NetFlow
   d. SPAN

Answer 1

c. The NetFlow standard provides session information including the source and destination addresses, applications, and traffic volume.

Question 2

2. What networking protocol uses OIDs and MIBs for data collection?
   a. SPAN
   b. NetFlow
   c. Syslog
   d. SNMP

Answer 2

d. The Simple Network Management Protocol (SNMP) uses Organisational Identifiers (OIDs) and management information bases (MIBs) for collection and organisation of data.

Question 3

3. What is a below-standard frame size called?
   a. Undercount
   b. Runt
   c. Nibble
   d. Short Frame

Answer 3

b. An Ethernet frame below the standard size of 64 bytes is a runt.

Question 4

4. What is one-way traffic flow called?
   a. Duplex
   b. Asymmetric
   c. Half-duplex
   d. Receive only auto-negotiation

Answer 4

c. Data traffic that transmits and receives in only one direction at a time is referred to as half-duplex.

Question 5

5. What is the average of collected metrics called?
   a. NetFlow
   b. SNMPv2c
   c. Management information base
   d. Baseline
   e. syslog

Answer 5

d. A measurement is taken from network gear and servers to determine what is considered to be normal operations of a system.

Question 6

6. Which device components should never be allowed to reach full capacity? (choose two)
   a. Memory
   b. Voltage
   c. CPU
   d. Delay

Answer 6

a, c. When a system uses all available memory or CPU resources, it may become very unstable and fail. Devices must hav available memory and CPU capacity available to be able to function.

Question 7

7. Which of the following mathematically determines network errors?
   a. SNMP
   b. NetFlow
   c. CRC
   d. Syslog

Answer 7

c. A cyclic redundancy check or CRC, is a mathematical calculation of a frame of data that is sent to a remote device where it is also calculated and compared to calculation it received. If the values match, the frame was error free.

Question 8

8. What protocol is used to poll and collect information from network devices?
   a. SPAN
   b. NetFlow
   c. Syslog
   d. SNMP

Answer 8

d. The Simple Network Management Protocol (SNMP) is an application and protocol used to collect operational data from network devices.

Question 9

9. What is the term for when a segment of data fails the addition or deletion of header information?
   a. Encapsulation error
   b. CRC
   c. NetFlow
   d. Frame reject

Answer 9

a. An encapsulation error occurs when a software process fails to add or remove header data to/from a data frame.

Question 10

10. What are two environmental variables that are commonly monitored? (choose two)
    a. Temperature
    b. Airflow
    c. Humidity
    d. Utilisation

Answer 10

a, c. Data centres monitor the temperature and humidity to ensure they are in safe operating ranges to protect the equipment and to make sure they are within their heat and humidity specifications.

Question 11

11. Baselines commonly include which of the following?
    a. Processor
    b. Memory
    c. Storage subsystems
    d. Wired/wireless utilisation
    e. all of the above

Answer 11

e. A baseline can be taken on any metric that is considered to be critical for operations.

Question 12

12. What are two metrics that are attacked to account for utilisation in operations?
    a. Syslog
    b. Uptime
    c. Downtime
    d. SNMP

Answer 12

b, c. Utilisation metrics include tracking both the uptime and downtime of applications, servers, and networking gear.

Question 13

13. What is a system-design protocol that guarantees a certain amount of operational uptime during a given period?
    a. High availability
    b. Redundancy
    c. Hot Standby
    d. Backup systems

Answer 13

a. High availability is an architecture that enhances a device’s ability to operate even if a component or software process fails.

Question 14

14. What is bi-directional traffic flow across an ethernet interface?
    a. Full-duplex
    b. Two-way
    c. Duplex
    d. Symmetric

Answer 14

a. Traffic that flows in both directions simultaneously is referred to as full duplex.

Question 15

15. What syslog severity level denotes that the system is unusable?
    a. Emergency
    b. Alert
    c. Critical
    d. Error

Answer 15

a. The emergency syslog severity level is the most critical and means that a system may be down or unusable.

Question 16

16. What protocol is commonly used to collect audit information?
    a. SNMP
    b. NetFlow
    c. Syslog
    d. Kibana

Answer 16

c. The syslog protocol provides a record of system events and is helpful in reviewing events over time.

Question 17

17. Which SNMP version added support for GET BULK operations?
    a. SNMPv1
    b. SNMPv2a
    c. SNMPv2c
    d. SNMPv3

Answer 17

c. SNMP version 2c added support for GET BULK, which greatly reduced network traffic. Instead of a network management station requesting objects one at a time, GET BULK allows for multiple objects to be fetched in one request.

Question 18

18. What is the variation in delay?
    a. Jitter
    b. Bandwidth variance
    c. Latency
    d. Egress latency

Answer 18

a. When data arrives with delays that increase and decrease, there is jitter along the transmission path. This is very detrimental to jitter-sensitive applications such as voice and video.

Question 19

19. What is end-to-end delay?
    a. Jitter
    b. Bandwidth variance
    c. Latency
    d. Egress latency

Answer 19

c. Latency is the measurement of end-to-end delay

Question 20

20. Resource starvation of which of the following can cause networking devices to fail?
    a. Memory
    b. bandwidth
    c. CRC utilisation
    d. CPU utilisation

Answer 20

a, d. Both high memory and CPU utilisation can cause network equipment such as routers and switches to not have available resources to operate and they may therefor fail or reload.