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IPV4 Addressing

Subject : it-skills

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. What is the other name for the TCP Header Length field?
Router(config-if)#no ip proxy-arp
Sequence Numbers
Loose source routing; Strict source routing; Record route; Timestamp
Data Offset

2. What is FIN?
Electrical/Optical - Mechanical - Functional and Procedural
Final
Version (4-bit); Header Length (4-bit); ToS (8-bit); Total Length (16-bit); Identifier (16-bit); Flags (3-bit); Fragment Offset (13-bit); TTL (8-bit); Protocol (8-bit); Header Checksum (16-bit); Source Address (32-bit); Destination Address (32-bit);
Router Selection

3. What is ECE?
Identifier; Flags and Fragmentation Offset
ICANN and IANA
Number of octets to be added to the Sequence Number to indicate the end of the urgent data
ECN-Echo

4. What mechanism is used by TCP to regulate the flow of segments?
Windowing
0x0800
RFC 791
The next sequence number that the source expects to receive from the destination

5. Adds a permanent static ARP entry for an Ethernet host
Router(config)#arp {ip-address} {mac-address} arpa
Identifier; Flags and Fragmentation Offset
9
Router#debug arp

6. What is the function of ICMP redirect messages?
8
IANA
Used by routers to notify hosts of another router on the data link that should be used for a particular destination
Network interface

7. What is the format of the ToS field?
Minimize Delay (1-bit); Maximise Throughput (1-bit); Maximise Reliability (1-bit); Minimize Monetary Cost (1-bit)
Data Offset
ICANN and IANA
Transmission Control Protocol

8. Which IPv4 address range is reserved for use in documentation and example code?
Protocols that don't include subnet masks in their routing updates
192.0.2.0/24
88
National Internet Registry

9. What is the recommended default TTL?
64
Socket
Application
Both the TCP header and the encapsulated data

10. What is the content of the Maximum Segment Size (MSS) in the Option field of the TCP header?
ICANN and IANA
Push
Largest segment size that the sender is willing to accept
192.0.2.0/24

11. What is the most commonly used Option field in the TCP header?
Each router decrements the TTL
Regional Internet Registry
Mostly large ISPs - enterprises - or academic institutions
Maximum Segment Size (MSS)

12. What is the name of the queuing and forwarding of IP packets based on DiffServ?
They are the same byte - but the names and value interpretations are different
Per-Hop Behaviour (PHB)
89
Uniquely identify every application in the network

13. Enables debugging output for ARP transactions
ECN-Echo
Router#debug arp
Synchronize
Reset

14. What is the minimum length of an IPv4 header?
Minimize Delay (1-bit); Maximise Throughput (1-bit); Maximise Reliability (1-bit); Minimize Monetary Cost (1-bit)
Windowing
20 octets
Largest segment size that the sender is willing to accept

15. What TCP/IP protocol suite layer corresponds to the session - presentation and application layers of the OSI model?
Internet Protocol
Application
4
Each router decrements the TTL

16. What is the ARP Operation value for a Reverse ARP Reply?
Padding of zeros to ensure that the header ends on a 32-bit boundary
Transmission Control Protocol
4
Router#clear arp-cache [{interface {interface}} | {ip-address}]

17. Displays the ARP cache of a router
They are the same byte - but the names and value interpretations are different
Router(config)#ip arp proxy disable
Router(config)#ip netmask-format {bit-count | decimal | hexadecimal}
Router#show arp

18. What is the TTL field in the IPv4 header?
Sequence Number + Data payload octets + 1
Time to Live
1-2 Network interface; 3 Internet; 4 Host-to-host; 5-7 Application
Internet Corporation for Assigned Network Numbers

19. What is ISP?
Internet Service Provider
Used by routers to notify hosts of another router on the data link that should be used for a particular destination
Maximum Segment Size (MSS)
IANA

20. What is added after the Option field in the TCP header?
Used by a host to obtain the IP address associated with another host's MAC address
Reset
Padding of zeros to ensure that the header ends on a 32-bit boundary
Subtract Header Length field from Total Length field

21. How does the layers of the TCP/IP protocol suite map to the 7 layers of the OSI model?
0x0800
DSCP (6-bit); ECN (2-bit)
Sequence Number
1-2 Network interface; 3 Internet; 4 Host-to-host; 5-7 Application

22. Who is responsible for maintaining the official assignments of TCP and UDP port numbers for specific uses?
IANA
Per-Hop Behaviour (PHB)
6
RIRs

23. What is ICMP Type 10?
RIPv1 and IGRP
Regional Internet Registry
Router Selection
Don't Fragment

24. Disables proxy ARP on an interface
Router(config-if)#no ip proxy-arp
Router#debug arp
RIRs
Internet Service Provider

25. What are the IP Precedence values?
0 Routine; 1 Priority; 2 Immediate; 3 Flash; 4 Flash Override; 5 Critical; 6 Internetwork Control; 7 Network Control
1-2 Network interface; 3 Internet; 4 Host-to-host; 5-7 Application
Final
Internet Control Message Protocol

26. What is SYN?
They are the same byte - but the names and value interpretations are different
Sequence Number + Data payload octets + 1
Synchronize
1 Determine how many subnets are required; 2 Determine how many hosts per subnet are required; 3 Determine the subnet mask for each subnet; 4 Calculate the network address for each subnet

27. Disables proxy ARP on all interfaces
64
Router(config)#ip arp proxy disable
Push
ECN-Echo

28. What TCP/IP protocol suite layer corresponds to the transport layer of the OSI model?
255.255.255.192
An ARP request issued by a host with its own IPv4 address as the target address
Host-to-host
4

29. Which IPv4 address range is reserved for IPv6 to IPv4 (6to4) relays (RFC 3068)?
Identifier; Flags and Fragmentation Offset
Echo
192.88.99.0/24
Internet Control Message Protocol

30. What is ICMP Type 5?
192.88.99.0/24
ICMP Router Discovery Protocol
Redirect
IP Precedence (3-bit); ToS (4-bit); Reserved (1-bit)

31. What is the ARP Operation value for an Inverse ARP Request?
169.254.0.0/16
0
Mostly large ISPs - enterprises - or academic institutions
8

32. What is the format of the Flags field in the IPv4 header?
Reserved (1-bit); DF (1-bit); MF (1-bit)
Used by a host to obtain the IP address associated with another host's MAC address
All Internet Registries
RIRs

33. What is TCP?
4
Internet Service Provider
Transmission Control Protocol
255.255.255.248

34. What is LIR?
89
Destination Unreachable
Source Port (16-bit); Destination Port (16-bit); UDP Length (16-bit); Checksum (16-bit)
Local Internet Registry

35. What is the first octet rule for IPv4 address classes in binary?
Class A 0; Class B 10; Class C 110; Class D 1110; Class E 1111
Minimize Delay (1-bit); Maximise Throughput (1-bit); Maximise Reliability (1-bit); Minimize Monetary Cost (1-bit)
Echo
IANA

36. What is ACK?
They are the same byte - but the names and value interpretations are different
Router(config)#arp {ip-address} {mac-address} arpa
Acknowledgement
National Internet Registry

37. What is prefix /26 in decimal notation?
255.255.255.192
0
Acknowledgement
NIRs

38. What is ICMP Type 0?
Address Resolution Protocol
Echo Reply
Method where routers - by responding to ARP requests for IP addresses in different subnets - make themselves available to hosts with no default gateway configured
Used by a host to obtain the IP address associated with another host's MAC address

39. What is ARP?
Acknowledgement
2
Duplicate address checks; Advertise new data-link identifiers; Update the ARP caches of hosts
Address Resolution Protocol

40. What is prefix /27 in decimal notation?
255.255.255.224
Address Resolution Protocol
127.0.0.0/8
Length of header in words (32-bit)

41. What is the format of the ToS byte in the IPv4 header?
Largest segment size that the sender is willing to accept
IP Precedence (3-bit); ToS (4-bit); Reserved (1-bit)
255.255.255.252
Router(config)#ip netmask-format {bit-count | decimal | hexadecimal}

42. Specifies the format in which subnet masks are displayed in show command output
6
Offset - in units of eight octets - from the beginning of the original header to the beginning of the fragment
Loose source routing; Strict source routing; Record route; Timestamp
Router(config)#ip netmask-format {bit-count | decimal | hexadecimal}

43. What are the most common IP version numbers?
Reserved (1-bit); DF (1-bit); MF (1-bit)
IPv4 and IPv6
3
Identifier; Flags and Fragmentation Offset

44. What is URG?
10.0.0.0/8; 172.16.0.0/12; 192.168.0.0/16
Urgent
Length of header in words (32-bit)
Class A 1-126; Class B 128-191; Class C 192-223; Class D 224-239; Class E 240-254

45. Which IPv4 address range is reserved for self-identification on a local subnet?
ICANN
Class A 0; Class B 10; Class C 110; Class D 1110; Class E 1111
0.0.0.0/8
Router(config)#arp {ip-address} {mac-address} arpa

46. What TCP/IP protocol suite layer corresponds to the network layer of the OSI model?
Internet
20 octets
Sequence Number + Data payload octets + 1
255.255.255.224

47. Configures how long a dynamically learned protocol address and its corresponding hardware address remains in the ARP cache
Push
255.255.255.252
0
Router(config-if)#arp timeout {seconds}

48. What is RST?
Open Systems Interconnection
3
Reset
Internet Assigned Numbers Authority

49. What mechanisms are used by TCP to provide reliable segment delivery?
Acknowledgements - checksums and timers
Duplicate address checks; Advertise new data-link identifiers; Update the ARP caches of hosts
Method where routers - by responding to ARP requests for IP addresses in different subnets - make themselves available to hosts with no default gateway configured
Router(config-if)#arp timeout {seconds}

50. What is IRDP?
Acknowledgements - checksums and timers
Urgent
ICMP Router Discovery Protocol
RIPv1 and IGRP