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Cisco Network Fundamentals - 2

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. ACK is?
Maximum transmission unit
Acknowledgment field significant
An alternate HTTP port
20 and 8

2. Why does TCP use a sequence number in the header?
Netstat -r and route print
Routing table
To reassemble the segments into data - To identify the application layer protocol - To indicate the number of the next expected byte - To show the maximum number of bytes allowed during a session. Allows the receiving host to reassemble segments in p
Web browsing - email - file transfer

3. When an OSI Layer 4 PDU has been encapsulated at the network layer it is called a ______________.
It means ensuring that each segment that the source sends arrives at the destination
Packet
Web browsing - email - file transfer
The default gateway address is the address of a router interface that is connected to the same network as the host.

4. What four tasks does the network layer perform?
2nd and third choices are correct--TCP is reliable and connection-oriented. IP is the one that's unreliable and connectionless. IP operates at the network layer.
It is the most common - and it encapsulates transport layer segments
Yes - for applications and services such as http - pop - smtp. Client requests services from a specific port.
Addressing packets with IP addresses - Encapsulation - Routing - Decapsulation

5. Which of the following are true about IP?
It is the most common - and it encapsulates transport layer segments
128
Synchronize sequence numbers
It means ensuring that each segment that the source sends arrives at the destination

6. What are the transport layer's responsibilities?
53
Keeping track of the individual conversations taking place between applications on the source and destinations hosts - Segmenting data and adding a header - Using header info to reassemble the segments into application data - Passing the assembled da
SMTP
Allows the transport layer function on the destination host to reassemble segments in the right order

7. Which of the following are true about network layer encapsulation?
It adds a header - and adds both source and destination IP addresses. Network layer encapsulation happens only on the original host; other devices can read the data - but they do not remove or alter it until the destination network is reached.
Acknowledgment and reassembly (receipt of packets and putting them in right order)
Delivery reliability and application data analysis. The first is a transport layer concern - and the second is the presentation layer. Routing - addressing packets with an IP adress - encapsulation and decapsulation are functions of the network layer
Synchronize sequence numbers

8. Port 443 is?
HTTPS (Secure HTTP)
It works the same on all Layer 1 media
1
Delivery reliability and application data analysis. The first is a transport layer concern - and the second is the presentation layer. Routing - addressing packets with an IP adress - encapsulation and decapsulation are functions of the network layer

9. During data transfer - What is the receiving host responsible for?
The default gateway address is the address of a router interface that is connected to the same network as the host.
1024. The lower numbers are the well-known ports.1024 through 49151 are registered ports and used by the host for dynamic port allocation
Acknowledgment and reassembly (receipt of packets and putting them in right order)
1

10. The three main features of routes in a routing table are?
It Doesn't - TCP does
Decapsulation
Destination network - next-hop - metric
It means ensuring that each segment that the source sends arrives at the destination

11. How many bits are in an IPv6 address?
FIN -> FIN.ACK (terminate client to server) - FIN->FIN.ACK->Ack recvd (terminate server to client)
128
Data link - physical
TFTP - Trivial File Transfer Protocol

12. Which characteristics are part of TCP? Pick two: Reliable - connectionless - no flow control - resends anything not received?
Reliable - connection-oriented protocol (resends if not received)
Upper
20 and 8
UDP

13. Port 520 is?
Connectionless
IP. TCP is connection-oriented - and UDP is connectionless but works on the transport layer.
RIP (Routing Information Protocol)
Web browsing - email - file transfer

14. When the client end of the session has no more data to transfer - it sets the ___________ flag in the header of the segment? (Hint: three-letter acronym)
FIN
SMTP
It is used by both routers and hosts. The second one is incorrect because IP uses addressing information in the header to determine the best path for the packet. 'Reliable' is incorrect because IP is only a 'best effort' protocol
0 - 1023 (total of 1024). The Internet Assigned Numbers Authority (IANA) is responsible for maintaining the official assignments of port numbers for specific uses

15. SYN is?
Segmentation provides the means to send and receive data when running multiple applications concurrently on a computer
Synchronize sequence numbers
Packet
Acknowledgment and reassembly (receipt of packets and putting them in right order)

16. What is the name of the process of removing the OSI Layer 2 information from an IP packet?
TCP. It makes larger demands on a network
Source and destination (ports) - Sequencing - Acknowledgement - Flow control
Decapsulation
Acknowledgment and reassembly (receipt of packets and putting them in right order)

17. UDP stands for?
0 - 1023 (total of 1024). The Internet Assigned Numbers Authority (IANA) is responsible for maintaining the official assignments of port numbers for specific uses
Synchronize sequence numbers
User Datagram Protocol
IP. TCP is connection-oriented - and UDP is connectionless but works on the transport layer.

18. Pieces of information about a route that a routing table contains
Next hop - metric and destination network. Routers do not need source address - last hop - or default gateway to find a path to the network.
The default gateway address is the address of a router interface that is connected to the same network as the host.
An alternate HTTP port
2nd and third choices are correct--TCP is reliable and connection-oriented. IP is the one that's unreliable and connectionless. IP operates at the network layer.

19. What is the port range for well known ports
HTTPS (Secure HTTP)
FTP
0 - 1023 (total of 1024). The Internet Assigned Numbers Authority (IANA) is responsible for maintaining the official assignments of port numbers for specific uses
1024 - 49151. Unlike ports with lower numbers - developers of new TCP/UDP services can select a specific number to register with IANA rather than having a number assigned to them. Using registered ports also avoids the additional security restriction

20. Which is a connection-oriented protocol - TCP or UDP?
TCP
UDP
20 and 8
Delivery reliability and application data analysis. The first is a transport layer concern - and the second is the presentation layer. Routing - addressing packets with an IP adress - encapsulation and decapsulation are functions of the network layer

21. Port 25 is?
Ephermeral
SMTP
17 (A flag is set in the segment header. If this flag actually reads 17 - it is identified as a UDP header)
1024. The lower numbers are the well-known ports.1024 through 49151 are registered ports and used by the host for dynamic port allocation

22. What are the three basic characteristics of IPv4?
The source and destination port number
It is the most common - and it encapsulates transport layer segments
Yes - for applications and services such as http - pop - smtp. Client requests services from a specific port.
Connectionless - Best effort (unreliable) - media independent

23. What does segmentation provide to communications?
1024 - 49151. Unlike ports with lower numbers - developers of new TCP/UDP services can select a specific number to register with IANA rather than having a number assigned to them. Using registered ports also avoids the additional security restriction
Segmentation provides the means to send and receive data when running multiple applications concurrently on a computer
Static routing
10.0.0.0/8 10.0.0.0 to 10.255.255.255 - 172.16.0.0/12 172.16.0.0 to 172.31.255.255 - 192.168.0.0/16 192.168.0.0 to 192.168.255.255

24. Port 23 is?
Reliable - connection-oriented protocol (resends if not received)
TCP uses flow control
Telnet
Dynamic / private

25. Port 8080 is?
DNS - video-streaming - VoIP
Dynamic / private
An alternate HTTP port
Transport

26. The value of the ACK number field is equal to the client ISN plus ___________ (number)?
An alternate HTTP port
17 (A flag is set in the segment header. If this flag actually reads 17 - it is identified as a UDP header)
1
Yes - for applications and services such as http - pop - smtp. Client requests services from a specific port.

27. When an IP packet is decapsulated - the information in the packet is handed to the upper or lower layers for delivery and processing?
Upper
UDP
17 (A flag is set in the segment header. If this flag actually reads 17 - it is identified as a UDP header)
Forward the packet to the default route interface (gateway) or just drop/discard the packets

28. List three network applications that use UDP
17 (A flag is set in the segment header. If this flag actually reads 17 - it is identified as a UDP header)
1
DNS - video-streaming - VoIP
TCP

29. If a router needs to send a packet but doesn't know the next hop or destination network - what can it do?
Forward the packet to the default route interface (gateway) or just drop/discard the packets
Decapsulation
Destination network - next-hop - metric
Connectionless - Best effort (unreliable) - media independent

30. How many bytes of overhead do TCP segments carry? How many does UDP carry?
It works the same on all Layer 1 media
Data link - physical
20 and 8
All

31. What are three key factors to consider when grouping hosts into a common network?
Purpose - ownership - and geographic location are key ways to divide a network
Routing table
Static routing
32 - there are four octets of 8 bits each in an IPv4 address

32. Which is a connectionless protocol - UDP or TCP?
Yes - for applications and services such as http - pop - smtp. Client requests services from a specific port.
RIP (Routing Information Protocol)
Destination device is there - Figures out if it has an active service running and is accepting requests on the right port - Tells the destination device that it wants to communicate on said port
UDP

33. MSN messenger uses TCP or UDP?
TCP
0 - 1023 (total of 1024). The Internet Assigned Numbers Authority (IANA) is responsible for maintaining the official assignments of port numbers for specific uses
All
A broadcast domain is a logical part of a network (a network segment) in which any network equipment can transmit data directly to another equipment or device without going through a routing device (assuming the devices share the same subnet and use

34. Why is IP 'media independent'?
0 - 1023 (total of 1024). The Internet Assigned Numbers Authority (IANA) is responsible for maintaining the official assignments of port numbers for specific uses
53
Dynamic / private
It works the same on all Layer 1 media

35. How many bits are in an IPv4 address?
32 - there are four octets of 8 bits each in an IPv4 address
Acknowledgment and reassembly (receipt of packets and putting them in right order)
Upper
10.0.0.0/8 10.0.0.0 to 10.255.255.255 - 172.16.0.0/12 172.16.0.0 to 172.31.255.255 - 192.168.0.0/16 192.168.0.0 to 192.168.255.255

36. What kinds of problems are caused by excessive broadcast traffic on a network segment?
Reduced network bandwidth - increased overhead - and reduced host functions. The other answers are part of solutions to excessive broadcasts
53
Decapsulation
It works the same on all Layer 1 media

37. What is the purpose of TCP/UDP port numbers?
20 and 8
It adds a header - and adds both source and destination IP addresses. Network layer encapsulation happens only on the original host; other devices can read the data - but they do not remove or alter it until the destination network is reached.
To track the different conversations crossing the network at the same time
Ephermeral

38. What is the protocol number for UDP?
Netstat lists the protocols in use - the local address and port number - the foreign address and port number - and the state of the connection. Also displays active TCP connections - ports on which the computer is listening - Ethernet statistics - th
17 (A flag is set in the segment header. If this flag actually reads 17 - it is identified as a UDP header)
20 and 8
Upper

39. Which of the following are not functions of the network layer?
Dynamic / private
128
Delivery reliability and application data analysis. The first is a transport layer concern - and the second is the presentation layer. Routing - addressing packets with an IP adress - encapsulation and decapsulation are functions of the network layer
Does not

40. What is the default DNS port number?
53
1
17 (A flag is set in the segment header. If this flag actually reads 17 - it is identified as a UDP header)
UDP - it sends datagrams as 'best effort'

41. What is the proper order of FIN sequence?
To reassemble the segments into data - To identify the application layer protocol - To indicate the number of the next expected byte - To show the maximum number of bytes allowed during a session. Allows the receiving host to reassemble segments in p
FIN -> FIN.ACK (terminate client to server) - FIN->FIN.ACK->Ack recvd (terminate server to client)
Reliable - connection-oriented protocol (resends if not received)
Decapsulation

42. Ephermeral port is what type of port
FIN
Destination network - next-hop - metric
Dynamic / private
It means ensuring that each segment that the source sends arrives at the destination

43. Are well known ports registered
Not - these are done by other protocols in other layers
TCP
Window size
Yes - for applications and services such as http - pop - smtp. Client requests services from a specific port.

44. The router a network uses to send and receive messages beyond the network is called a ___________ router.
Does not
It is used by both routers and hosts. The second one is incorrect because IP uses addressing information in the header to determine the best path for the packet. 'Reliable' is incorrect because IP is only a 'best effort' protocol
32 - there are four octets of 8 bits each in an IPv4 address
Gateway

45. Which of the following are true about static and dynamic routing?
32 - there are four octets of 8 bits each in an IPv4 address
It is the most common - and it encapsulates transport layer segments
Dynamic routing adds packet-processing overhead - and routers can use static and dynamic routing simultaneously
UDP

46. Routers add routes for the connected networks to their ________________ .
Acknowledgment and reassembly (receipt of packets and putting them in right order)
Routing table
User Datagram Protocol
Dynamic routing adds packet-processing overhead - and routers can use static and dynamic routing simultaneously

47. Which of the following is true about IP?

48. What is a broadcast domain?
Acknowledgment field significant
A broadcast domain is a logical part of a network (a network segment) in which any network equipment can transmit data directly to another equipment or device without going through a routing device (assuming the devices share the same subnet and use
Purpose - ownership - and geographic location are key ways to divide a network
Delivery reliability and application data analysis. The first is a transport layer concern - and the second is the presentation layer. Routing - addressing packets with an IP adress - encapsulation and decapsulation are functions of the network layer

49. UDP does or does not create a session?
DNS - video-streaming - VoIP
Delivery reliability and application data analysis. The first is a transport layer concern - and the second is the presentation layer. Routing - addressing packets with an IP adress - encapsulation and decapsulation are functions of the network layer
Does not
SYN -> SYN.ACK->SEQ - ACK = SEQ+1 - SEQ is a random #

50. What is the purpose of the ToS field in the IPv4 header?
20 and 8
The type-of-service field contains an 8-bit binary value that is used to determine the priority of each packet. This enables QoS (Quality of service) to happen.
17 (A flag is set in the segment header. If this flag actually reads 17 - it is identified as a UDP header)
Netstat -r and route print