1. Which OSI layer sends segments to be encapsulated in an IPv4 or IPv6 packet?

  • A. Data link layer
  • B. Network layer
  • C. Transport layer
  • D. Session layer

2. Which layer is responsible for taking an IP packet and preparing it for transmission over the communications medium?

  • A. Data link layer
  • B. Network layer
  • C. Transport layer
  • D. Session layer

3. What is the term for splitting up an IP packet when forwarding it from one medium to another medium with a smaller MTU?

  • A. Encapsulation
  • B. Fragmentation
  • C. Segmentation
  • D. Serialization

4. Which delivery method does not guarantee that the packet will be delivered fully without errors?

  • A. Connectionless
  • B. Best effort
  • C. Media independent

5. What are the two most commonly referenced fields in an IPv4 packet header that indicate where the packet is coming from and where it is going? (Choose two.)

  • A. Destination IP address
  • B. Protocol
  • C. Time to Live
  • D. Source IP address
  • E. Differentiated Services (DS)

6. Which statement is correct about IPv4 packet header fields?

  • A. The source and destination IPv4 addresses remain the same while travelling from source to destination.
  • B. The Time to Live field is used to determine the priority of each packet.
  • C. The Total Length and Header Checksum fields are used to reorder a fragmented packet.
  • D. The Version field identifies the next level protocol.

7. Which field is used to detect corruption in the IPv4 header?

  • A. Header Checksum
  • B. Time to Live
  • C. Protocol
  • D. Differentiated Services (DS)

8. Which field includes common values such as ICMP (1), TCP (6), and UDP (17)?

  • A. Header Checksum
  • B. Time to Live
  • C. Protocol
  • D. Differentiated Services (DS)

9. Which three options are major issues associated with IPv4? (Choose three.)

  • A. IP address depletion
  • B. Increased network complexity and Internet routing table expansion
  • C. Always on connections
  • D. Lack of end-to-end connectivity
  • E. Global and political boundaries
  • F. Too many IPv4 addresses available

10. Which two options are improvements provided by IPv6 as compared to IPv4? (Choose two.)

  • A. Header supports additional fields for complex packets
  • B. Increased the IP address space
  • C. Standardizes the use of NAT
  • D. Supports class-based networks
  • E. Uses a simpler header to provide improved packet handling

11. Which is true of the IPv6 header?

  • A. It consists of 20 octets.
  • B. It consists of 40 octets.
  • C. It contains 8 header fields.
  • D. It contains 12 header fields.

12. Which is true of the IPv6 packet header?

  • A. The Hop Limit field replaces the IPv4 Time to Live field.
  • B. The Source and Destination IPv6 addresses change while travelling from source to destination.
  • C. The Time to Live field replaces the DiffServ field.
  • D. The Version field identifies the next header.

13. Which statement about host forwarding decisions is true?

  • A. A host cannot ping itself.
  • B. A remote destination host is on the same local network as the sending host.
  • C. Local hosts can reach each other without the need of a router.
  • D. Routing is enabled on switches to discover the best path to a destination.

14. Which default gateway statement is true?

  • A. A default gateway is required to send packets to other hosts on the local network.
  • B. The default gateway address is the IP address of a switch on a remote network.
  • C. The default gateway address is the IP address of the router on the local network.
  • D. Traffic can only be forwarded outside the local network if there is no default gateway.

15. Which two commands could be entered on a Windows host to view its IPv4 and IPv6 routing table? (Choose two.)

  • A. Netroute –l
  • B. Netstat -r
  • C. Print route
  • D. Route print
  • E. Print net

16. What is the command used on a Cisco IOS router to view the routing table?

  • A. Netstart –r
  • B. Route print
  • C. Show ip route
  • D. Show routing table

17. What does a code of “O” indicate next to a route in the routing table?

  • A. A directly connected route
  • B. A route with an administrative distance of 0
  • C. A gateway of last resort
  • D. A route learned dynamically from OSPF

18. This type of route is also known as a gateway of last resort.

  • A. Static route
  • B. Remote route
  • C. Default route
  • D. Directly connected route

19. Which is a characteristic of static routes?

  • A. They are manually configured.
  • B. They are advertised to directly connected neighbors.
  • C. They are appropriate when there are many redundant links.
  • D. They automatically adjust to a change in network topology.

20. True or False? A router can be configured with a combination of both static routes and a dynamic routing protocol.

  • A. True
  • B. False

21. Which command can be used on a Windows host to display the routing table?

  • A. Tracert
  • B. Netstat –s
  • C. Netstat –r
  • D. Show ip route

On a Windows host, either the route print or netstat -r commands can be used to display the host routing table. The show ip route command is used on a router to display its routing table. The netstat –s command is used to display per-protocol statistics. The tracert command is used to display the path that a packet travels to its destination.

22. What information is added during encapsulation at OSI Layer 3?

  • A. Source and destination IP address
  • B. Source and destination MAC
  • C. Source and destination application protocol
  • D. Source and destination port number

IP is a Layer 3 protocol. Layer 3 devices can open the Layer 3 header to inspect the Layer 3 header which contains IP-related information including the source and destination IP addresses.

23. How does the network layer use the MTU value?

  • A. The network layer depends on the data link layer to set the MTU, and adjusts the speed of transmission to accommodate it.
  • B. To increase speed of delivery, the network layer ignores the MTU.
  • C. The network layer depends on the higher level layers to determine the MTU.
  • D. The MTU is passed to the network layer by the data link layer.

The data link layer indicates to the network layer the MTU for the medium that is being used. The network layer uses that information to determine how large the packet can be when it is forwarded. When packets are received on one medium and forwarded on a medium with a smaller MTU, the network layer device can fragment the packet to accommodate the smaller size.

24. Which characteristic describes an IPv6 enhancement over IPv4?​

  • A. Both IPv4 and IPv6 support authentication, but only IPv6 supports privacy capabilities.
  • B. IPv6 addresses are based on 128-bit flat addressing as opposed to IPv4 which is based on 32-bit hierarchical addressing.
  • C. The IPv6 header is simpler than the IPv4 header is, which improves packet handling.
  • D. The IPv6 address space is four times bigger than the IPv4 address space.​

IPv6 addresses are based on 128-bit hierarchical addressing, and the IPv6 header has been simplified with fewer fields, improving packet handling. IPv6 natively supports authentication and privacy capabilities as opposed to IPv4 that needs additional features to support those. The IPv6 address space is many times bigger than IPv4 address space.

25. Which statement accurately describes a characteristic of IPv4?

  • A. An IPv4 header has fewer fields than an IPv6 header has.​
  • B. IPv4 natively supports IPsec.​
  • C. IPv4 has a 32-bit address space.
  • D. All IPv4 addresses are assignable to hosts.​

IPv4 has a 32-bit address space, providing 4,294,967,296 unique addresses, but only 3.7 billion are assignable, a limit due to address reservation for multicasting and testing. IPv4 does not provide native support for IPsec. IPv6 has a simplified header with fewer fields than IPv4 has.

26. When a router receives a packet, what information must be examined in order for the packet to be forwarded to a remote destination?

  • A. Destination IP address
  • B. Destination MAC address
  • C. Source IP address
  • D. Source MAC address

When a router receives a packet, it examines the destination address of the packet and uses the routing table to search for the best path to that network.

27. A computer has to send a packet to a destination host in the same LAN. How will the packet be sent?

  • A. The packet will be sent to the default gateway first, and then, depending on the response from the gateway, it may be sent to the destination host.
  • B. The packet will be sent directly to the destination host.
  • C. The packet will be sent only to the default gateway.
  • D. The packet will first be sent to the default gateway, and then from the default gateway it will be sent directly to the destination host.

If the destination host is in the same LAN as the source host, there is no need for a default gateway. A default gateway is needed if a packet needs to be sent outside the LAN.

28. Which IPv4 address can a host use to ping the loopback interface?

  • A. 127.0.0.1
  • B. 126.0.0.0
  • C. 127.0.0.0
  • D. 126.0.0.1

A host can ping the loopback interface by sending a packet to a special IPv4 address within the network 127.0.0.0/8.

29. When a connectionless protocol is in use at a lower layer of the OSI model, how is missing data detected and retransmitted if necessary?

  • A. Upper-layer connection-oriented protocols keep track of the data received and can request retransmission from the upper-level protocols on the sending host.
  • B. Network layer IP protocols manage the communication sessions if connection-oriented transport services are not available.
  • C. Connectionless acknowledgements are used to request retransmission.
  • D. The best-effort delivery process guarantees that all packets that are sent are received.

When connectionless protocols are in use at a lower layer of the OSI model, upper-level protocols may need to work together on the sending and receiving hosts to account for and retransmit lost data. In some cases, this is not necessary, because for some applications a certain amount of data loss is tolerable.

30. What was the reason for the creation and implementation of IPv6?

  • A.To provide more address space in the Internet Names Registry
  • B. To relieve IPv4 address depletion
  • C. To allow NAT support for private addressing
  • D. To make reading a 32-bit address easier

IPv4 addressing space is exhausted by the rapid growth of the Internet and the devices connected to the Internet. IPv6 expands the IP addressing space by increasing the address length from the 32 bits to 128 bits, which should provide sufficient addresses for future Internet growth needs for many years to come.

31. Which information is used by routers to forward a data packet toward its destination?

  • A. Source data-link address
  • B. Source IP address
  • C. Destination data-link address
  • D. Destination IP address

The destination IP address is the IP address for the receiving device. This IP address is used by routers to forward the packet to its destination.

32. Which field in an IPv4 packet header will typically stay the same during its transmission?

  • A. Flag
  • B. Destination Address
  • C. Time-to-Live
  • D. Packet Length

The value in the Destination Address field in an IPv4 header will stay the same during its transmission. The other options might change during its transmission.

33. Which field in an IPv6 packet is used by the router to determine if a packet has expired and should be dropped?

  • A. Hop Limit
  • B. TTL
  • C. Address Unreachable
  • D. No Route to Destination

ICMPv6, like IPv4, sends a Time Exceeded message if the router cannot forward an IPv6 packet because the packet has expired. However, the IPv6 packet does not have a TTL field. Instead, it uses the Hop Limit field to determine if the packet has expired.