Networking Chapter 6 – Questions

Flashcard maker : Lesly Ford
How many bits are the source and destination IPv4 addresses?
Both are 32 bits
What is the name for the decimal representation of the binary IP address called?
Dotted decimal notation
How many bits are there between each “dot”?
8 bits
Define the network portion of an IP address?
Some portion of the most significant bits, or high-order bits represent the network portion
What is the host portion of the IP address?
The remaining amount of available network addresses after the network portion is determined
What does the number of bits assigned to host determine?
Determines the number of total hosts within the network.
What is the binary range in decimal of a byte?
128-0
A special address that refers to the network
A special address used to send data to all hosts in the network.
The unicast addresses assigned to the end devices in the network.
What is the range where host addresses are assigned?
What is assigned to determine how many bits are in network bits?
A prefix length written in slash format
Do the number of hosts that can be assigned stay the same when prefix changes?
No
How do you calculate the network value?
All host bits are 0
How do you calculate the first host value?
By taking how many remaining bits you have from the prefix length and using the 2 to the power of that value minus 2.
The broadcast address uses the highest address in the network range, this is the address in which all of the bits in the host portion are all 1’s.
How do you calculate the last host address?
Using the remaining amount of available bits from the prefix length will allow you to calculate the last host address by setting all of the remaining bits to 1.
Unicast – the process of sending a packet from one host to an individual host
Broadcast – the process of sending a packet from one host to all hosts in the network
Multicast – the process of sending a packet from one host to a selected group of hosts
What is another name for a unicast address?
How does a host process a broadcast transmission?
It processes the packet as it would a packet to its unicast address.
What is a broadcast transmission used for?
The location of special services/devices for which the address is not known or when a host needs to provide information to all the hosts on the network.
What are the three examples of broadcast transmissions?
When does a host send a broadcast?
When a host needs information or needs to send information
How do hosts with the information usually respond to the broadcast?
One or more of the hosts will respond typically using unicast.
Useful for sending a broadcast to all hosts on a nonlocal network
What is a limited broadcast used for?
Used for communication that is limited to the hosts on the local network
What forms the boundary for a broadcast domain?
Router
What is multicast designed to do?
To conserve the bandwidth of the IPv4 network, it reduces traffic by allowing a host to send a single packet to a selected set of hosts.
What are the 4 examples of multicast transmissions?
Video and audio broadcasts, routing information exchange by some routing protocols, distribution of software, news feeds
They use services initiated by a client program to subscribe to the multicast group.
What is the range for multicast addresses?
224.0.0.0 – 239.255.255.255
What is the range for experimental addresses?
240.0.0.0 – 255.255.255.254
List the three private address blocks? (This is incredibly important for network administrators to know)
The private address block are: 10.0.0.0 – 10.255.255.255, 172.16.0.0 – 172.31.255.255, 192.168.0.0 – 192.168.255.255
What happens if a packet with a private IP address was sent to the Internet?
The routers would not have routes to forward them to the appropriate private network.
What is NAT Network Address Translation services used for?
How does NAT allow a host with a private address to access the Internet?
Allows the hosts in the private network to borrow a public address to communicate to outside networks.
169.254.0.0 – 169.254.255.255
Automatically assigned to the local host by the operating system in environments where no IP configuration is available.
What is the first octet range of Class A? B? C? D? E?
A – 1-127/ B – 128-191/ C – 192-223/ D – Multicast / E – Experimental
What is the limitation of classful routing?
What is the address system used today called?
Why should the allocation of addresses inside the networks be planned and documented for the purpose of?
Preventing duplication of addresses, providing and controlling access, monitoring security and performance
What are the different examples of types of hosts?
End devices for users, servers and peripherals, hosts that are accessible from the Internet, Intermediary devices
What considerations should be used about where private IP addresses should be used?
Which devices should have a static IP address? Why?
Printers, servers, and other networking devices that need to be accessible to clients. Because if hosts typically access a server at a particular IP address, it would cause problems if that address changed.
What does DHCP provide for an end device?
Automatic assignment of an IP address including subnet mask, and default gateway.
What is the block of addresses a DHCP server use called?
What does almost all traffic pass through when going between networks?
An intermediary device like a router.
Which IP addresses are used for router interfaces?
Usually the lowest or the highest address in the network but it should be uniform across all networks in a corporation.
What is the organization that assigns IP addresses in the US?
Internet Assigned Numbers Authority (IANA)
What are the advantages of having a Tier 1 ISP?
Reliability and speed, only one connection away from the Internet, fewer opportunities for failures or traffic bottlenecks.
What is the focus of a Tier 2 ISP?
Focus on business customers and usually offer more services than the other two tiers of ISPs
What is the focus of a Tier 3 ISP?
Focus on retail and home markets in a specific locale.
What was the main issue to be addressed by IPv6?
What were the other issues that were considered when developing IPv6?
Improved packet handling, increased scalability and longevity, quality of service (QoS) mechanisms, integrated security.
List the added features of IPv6.
128-bit hierarchical addressing to expand addressing capabilities, header format simplification to improve packet handling, improved support for extensions and options, flow-labeling capabilities as QoS mechanisms, authentication and privacy capabilities to integrate security
How is the subnet mask created?
You turn the network portion of the address into all 1s.
What is true if the octet of the subnet mask is 255?
Then the binary form of that octet is all 1s.
What is true if the octet of the subnet mask is 0?
Then the binary form of that octet is all Os
What is the result of the ANDing process?
What is the only case in which ANDing results in a 1?
What is ping?
A utility for testing IP connectivity between hosts.
What happens when the destination host receives an echo request?
It responds with an ICMP echo reply datagram
What is the address to ping the local host?
127.0.0.1
What does a response from the local host tell you?
Indicates that IP is properly installed on the host
What doesn’t the response from the local host tell you?
It doesn’t tell you an indication that the addresses, masks, or gateways are properly configured.
What does it tell you if a ping to the gateway is successful?
Indicates that the host and the router’s interface serving as that gateway are both operation and on the local network.
What does it tell you if a ping to the remote host is successful?
You will have verified the operation of a large piece of the internetwork.
What does the traceroute utility do?
Allows you to observe the path between these hosts, generates a list of hops that were successfully reached along the path.
Define Round Trip Time (RTT).
The time a packet takes to reach the remote host and for the response from the host to return, an asterisk is used to indicate a lost packet.
Define Time to Live (TTL).
A field in the IP header that prevents a packet from indefinitely looping around an IP internetwork.
What does ICMP provide for the TCP/IP protocol stack?
Provides control and error messages and is used by the ping and traceroute utilities
List the 5 ICMP messages that may be sent.
Host confirmation, Unreachable destination or service, Time exceeded, Route redirection, Source quench.