Troubleshooting Networks Flashcards
OBJ 5.7: Given a scenario, troubleshoot problems with wired and wireless networks
What are common causes of wired connectivity issues?
- Physical connection
- Cable length
- Interference
- Port flapping
What does the link light indicate in a wired connection?
Shows a valid link
What does the activity light indicate in a wired connection?
Blinks when sending or receiving data
What are the colors of the activity light and their corresponding speeds?
- Off: 10 Mbps
- Orange: 100 Mbps
- Green: 1000 Mbps
What is the purpose of a repeater in a network?
Used to increase the connectivity signal
What are common sources of interference in wired connections?
- Power lines
- Fluorescent lighting
- Motors
- Generators
What type of connections are used for network cables near power lines?
Fiber optic connections
What is port flapping?
Intermittent connectivity issue between the client and the network switch
What does the status of port flapping indicate?
Status changes from upstate to downstate
What are signs of network performance issues?
Manifesting the slowdown of network
Define half duplex in networking.
Network that sends or receives information
Define full duplex in networking.
Network that sends or receives information at the same time
What can cause data exfiltration?
- Mismatch in the duplex setting
- Mismatch in the speed setting
- Network adapter drivers are out of date
- Malware infection
What are common wireless connectivity issues?
- Intermittent wireless connectivity
- Signal interference
- Low signal strength
- Standards mismatch
What is the Received Signal Strength Indicator (RSSI)?
Used to measure the signal strength based on an index level
How is RSSI displayed?
In negative decibels
What are some solutions to improve signal strength?
- Increase the power of transmission
- Increase the antenna size
- Move closer to the source
What frequency bands are commonly used in wireless networking?
- 5 GHz: Wireless a, n, ac, ax
- 2.4 GHz: Wireless b, g, n
What is Voice Over Internet Protocol (VoIP)?
Set of protocols used to send streaming voice and video in real time
What is latency in networking?
Time it takes for a signal to reach the intended client
What is the recommended latency for VoIP?
Keep latency under 50 to 100 milliseconds
Define jitter in the context of networking.
Measurement of the variation in delay over time
What can cause jitter in a network?
When latency increases by up to 30-50 milliseconds
What is the impact of quality of service (QoS) settings?
Allows prioritization of voice traffic
What does limited connectivity indicate?
Specialized message to receive within the operating system
What are common causes of limited connectivity?
- Affects one network client
- DHCP issue
What components can be affected by a DHCP issue?
- IP address
- Subnet
- Default gateway
- DNS server IPs
