Network Management Flashcards
Network Management
o The process of administering and managing computer networks
Physical Network Diagram
Shows the actual physical arrangement of the components that make up
the network
Logical Network Diagram
Illustrates the flow of data across a network and shows how devices
communicate with each other
Wiring Diagram
Labels which cables are connected to which ports
Radio Frequency (Wireless) Site Survey
Planning and designing a wireless network to deliver the required
wireless solution
Audit and Assessment Report
▪ Delivered after a formal assessment has been conducted
● Audit and Assessment Report
o Executive summary
o Scope and objectives
o Assumptions and limitations
o Methods and tools
o Environment and system diagram
o Security requirements
o Findings and recommendations
o Audit results
Baseline Configurations
▪ Set of specifications for an information system, or a configuration item
within a system, that has been formally reviewed and agreed on
▪ Changes will be properly tested and approved to be part of the new
baseline
Network Performance Monitoring
▪ Monitors the performance from the end user’s workstation to the final
destination they are trying to reach
● Latency
o Time that it takes for data to reach its destination across a
network
o High latency slows down overall network performance
● Bandwidth
o Maximum rate of data transfer across a given network
● Throughput
o Actual measure of how much data is successfully
transferred from the source to a destination
● Jitter
o When a time delay in the sending of data packets over a
network connection occurs
▪ Ensure that your network is using QoS properly
Sensors
Monitors a device’s temperature, CPU usage, and memory, which could indicate
if it is operating properly or is about to fail
o Minor Temperature Threshold
▪ Used to set off an alarm when a rise in temperature is detected but
hasn’t reached dangerous levels yet
o Major Temperature Threshold
▪ Used to set off an alarm when temperature reaches dangerous
conditions
● 5-40% CPU utilization
o Misconfigured network
o Network under attack
▪ Minor
▪ Severe
▪ Critical
● 40%
o Normal conditions
● 60-70%
o Busier times
● Layer 3 80%
o Peak times
NetFlow Data
o Full Packet Capture is used to capture the entire packet, including the header
and the payload for all traffic entering and leaving a network
o Flow Analysis
▪ Relies on a flow collector to record the metadata and statistics about
network traffic rather than recording each frame
▪ Highlights trends and patterns
NetFlow
Defines a particular traffic flow based on the different packets that share
the same characteristics
● Protocol interface
● IP version/type
● Source/destination IP
● Source/destination port
● IP service type
Zeek
Passively monitors a network like a sniffer, but only logs full packet
capture data of potential interest
▪ Performs normalization of the data and stores it as a tab-delimited or
JSON-formatted text files
o Multi Router Traffic Grapher (MRTG)
Creates graphs showing traffic flows through the network interfaces of
routers and switches by polling the appliances using SNMP
Link State
Communicates whether a given interface has a cable connected to it and
a valid protocol to use for communication
Drop
Used to count the number of packets that have been dropped
Flush
▪ Used to count Selective Packet Discards (SPD) that have occurred
Selective Packet Discards (SPD)
Drops low priority packets when the CPU is too busy so it can save
capacity for higher priority packets as a form of QoS
Runt
An Ethernet frame that is less than 64 bytes in size
Giant
Any Ethernet frame that exceeds the 802.3 frame size of 1518 bytes
Throttle
Occurs when the interface fails to buffer the incoming packets
CRC
Number of packets received that failed the cyclic redundancy checksum,
or CRC check upon receipt
Frame
Used to count the number of packets where a CRC error and a noninteger number of octets was received
Overrun
Used to count how often the interface was unable to receive traffic due
to an insufficient hardware buffer
Ignored
Used to count the number of packets that the interface ignored since the
hardware interface was low on internal buffers
