Short Questions Flashcards
What do ICMP messages do?
Provides feedback about issues related to processing of IP packets
What ICMP messages do both IPv4 and IPv6 have?
Host Reachability, Destination or service unreachable and Time Exceeded
What two messages does Ping use?
ICMP Echo request and echo reply messages
Can test the internal configuration of ipv4 or ipv6
What does tracert do?
Generates a list of successfully reached hops along the specified path
What are characteristics of scalable networks
- They expand to support new users and applications
- They expand without degrading the performance of existing services
What does the router do?
Determines the path messages take through the network
What internet connection options do not require physical cables?
Cellular and Satellite connections
What do denial-of-service attacks do?
DOS attacks slow or crash processes on a network
List the types of clouds
- Private
- Public
- Community
- Hybrid
Which type of access is secured through the enable secret command
Privileged exec mode
What is the function of the shell in the OS?
The shell is the interface between the computer and the user, with the CLI and GUI to request tasks from the computer
What type of switch interface has no port associated with it?
Switch Virtual Interfaces have no physical ports
What type of communication sends messages to all devices on a LAN
Broadcast
What are three benefits of using a layered network model
- Prevents a technology that works in one layer from affecting another
- Assists in protocol design
- Visualises interactions between each layer
What is the purpose of message encoding?
Encoding converts data into a suitable format for transmission over the medium
What is done to an IP packet before it is transmitted over the physical medium?
The IP packet is encapsulated in a layer 2 (data link) frame
What is throughput
The measure of transfer of bits across the media over a given period of time. Is usually lower than bandwidth and measures overhead.
What feature automatically negotiates the best speed an duplex setting between interconnecting devices
Autonegotiation
List two methods for switching data between ports on a switch
- Store and forward
- Cut through switching
How does an ethernet switch build its MAC Address table?
A switch dynamically builds its MAC address table by examining the source MAC Addresses of the received frames on a port.
What improvements does IPv6 provide from IPv4
- Improved packet handling
- Increased address space
- Eliminates need for NAT
What field in an IPv4 packet is used by the router to determine if a packet has expired, and what field is used by IPv6 for the same?
IPv4 - Time To Live (TTL)
IPv6 - Hop Limit
What information is provided by the ARP when an IPv4 packet is sent to a remote host
ARP provides the MAC Address of the closest router interface to the sender
What are the two functions provided by ARP
- Resolve an IP address to its MAC address
- Maintain an ARP table which lists the pairs of addresses
