S27-Troubleshooting Performance issues

Question 1

Collision

Answer 1

two hosts on the network transmit at the same time causing signals to combine

Question 2

T/F Collisions can only occur on a wireless medium

Answer 2

False, Collisions can happen on wired and wireless networks

Question 3

Collision Domain

Answer 3

Network segment where simultaneous data transmissions collide with one another

Question 4

How can you detect collision on the network

Answer 4

• Experiencing poor network performance
• run show network interface command on your network device & look at port stats

Question 5

What can you do to overcome excessive collisions?

Answer 5

• Turn off Auto negotiation
• Hardcode lower speed
• change to half-duplex

Question 6

Broadcast Storm

Answer 6

Network system is overwhelmed by continuous multicast or broadcast traffic.

Question 7

what layers can a broadcast packet be addressed?

Answer 7

Layer 2 - FF:FF:FF:FF:FF:FF
Layer 3 - 255.255.255.255

Question 8

Broadcast Domain

Answer 8

A group of devices that can all receive broadcast messages from each other over layer 2.

Question 9

how do you breakup a Broad cast domain?

Answer 9

Using a router

Question 10

Causes for broad cast storms

Answer 10

• too large singular broadcast domain
• Large DHCP request volume
• Switching loops

Question 11

How can you identify a Broadcast storm?

Answer 11

• Large Spike in the packet counter
• frequent packet loss
• Use a packet analyzer and collect network traffic eg. via Wireshark or TCPdump

Question 12

Latency

Answer 12

Time it takes for a signal to reach the intended client

Question 13

Jitter

Answer 13

Variation in delay over time

Question 14

How can you reduce latency & Jitter?

Answer 14

• Increase network performance
• ## implement quality of service

Question 15

Ideal latency for quality VoIP service

Answer 15

under 50 - 100 ms

Question 16

Packet Loss

Answer 16

Data packets fails to reach their destination

Question 17

Common Packet Loss symptoms

Answer 17

• Unexplained network slowdowns
• VoIP jitter
• Abrupt Disconnections in media streaming

Question 18

What are some Factor associated with packet loss?

Answer 18

• Network Congestion
• Faulty Router Config
• Bad Cables
• Hardware Failures

Question 19

Network Congestion

Answer 19

Data sent through the network exceeds what the network can handle

Question 20

Faulty Router Config

Answer 20

Router is set up incorrectly resulting in misdirected and
mis-prioritized traffic

Question 21

what tools can you use to identify the source of packet loss?

Answer 21

• Ping command
• Traceroute/Tracert command
• Network monitoring tools

Question 22

Strategy to solve a network congestion issue

Answer 22

• Increase bandwidth
• Optimize network layout
• Employ QoS

Question 23

Strategy for Hardware issues

Answer 23

• Routine inspection
• Replace Faulty cables
• update firmware/drivers

Question 24

Common Causes of network performance issues

Answer 24

• High CPU usage
• High Bandwidth usage
• Poor connectivity
• Network malfunction
• DNS issues

Question 25

What analysis can you perform when assessing bandwidth usage?

Answer 25

Network Flow analysis

Question 26

Optical Link Budget

Answer 26

a calculation used to determine the maximum acceptable loss in a fiber optic link, ensuring a strong enough signal reaches the receiver

Question 27

What are some issues resulting from a low optical link budget?

Answer 27

- Reduced Transmission - Slow connection speeds - Connection downtime

Question 28

what is the standard dB per Km for fiber when using an Optical time reflectometer?

Answer 28

0.25 dB per km

Question 29

T/F A higher dB per km reading can be attributed to a low optical link budget

Answer 29

True

Question 30

Digital Certificate

Answer 30

Credential to facilitate verification of identities between users in a transaction