Chapter 4 - Fundamentals of IPv4 Addressing and Routing Flashcards
True or False. All IP addresses in the same group must not be separated from each other by a router.
True
True or False. IP addresses separated from each other by a router do not have to be in different groups.
False. IP addresses separated from each other by a router must be in different groups.
IP standards subdivide the entire address space into what 5 classes?
Classes A, B, C, D, and E
What does DDN stand for?
Dotted decimal notation
What address space is allocated to the Class A network?
Approximately one-half with addresses that start with 1-126.
What address space is allocated to the Class B network?
Approximately one-fourth with addresses that start with 128-191.
What address space is allocated to the Class C network?
Approximately one-eigth with addresses that start with 192-223.
What is the Class D network used for and what DDNs are assigned to it?
Used for multicast and it is assigned 224-239.
What is the Class E network used for and what DDNs are assigned to it?
Used for experimental and it is assigned 240-255.
Which DDN(s) are reserved?
0 and 127
How many networks in a Class A network - in the entire world?
126
How many networks in a Class B network - in the entire world?
16,384
How many networks in a Class C network - in the entire world?
2,097,152
How many hosts per Class A network?
16,777,214
How many hosts per Class B network?
65,534
How many hosts per Class C network?
254
What is the network number range for Class A networks?
1.0.0.0 to 126.0.0.0
What is the network number range for Class B networks?
128.0.0.0 to 191.255.0.0
What is the network number range for Class C networks?
192.0.0.0 to 223.255.255.0
What does the term classful IP network refer to?
Any Class A, B, or C network.
If the destination IP address is in the same IP subnet as the host, what does the sending host do with the packet?
Sends the packet directly to that destination host.
If the destination IP address is NOT in the same IP subnet as the host, what does the sending host do with the packet?
The host sends the packet to the default gateway also known as the default router.
What 4 step process does a router go through when it receives a data link frame addressed to that router’s data link address?
Step 1. Use the data link Frame Check Sequence (FCS) field to ensure that the frame had no errors; if errors occurred, discard the frame.
Step 2. Assuming that the frame was not discarded at Step 1, discard the old data link header and trailer, leaving the IP packet.
Step 3. Compare the IP packet’s destination IP address to the routing table, and find the route that best matches the destination address.
Step 4. Encapsulate the IP packet inside a new data link header and trailer, appropriate for the outgoing interface, and forward the frame.
What are some goals of a routing protocol?
1) To dynamically learn and fill the routing table with a route to each subnet in the internetwork.
2) If more than one route to a subnet is available, to place the best route in the routing table.
3) To notice when routes in the table are no longer valid, and to remove them from the routing table.
4) If a route is removed from the routing table and another route through another neighboring router is available, to add the route to the routing table.
5) To work quickly when adding new routes or replacing lost routes.
6) To prevent routing loops.
