Network Layer Characteristics Question Bank

Chapter 6 : Question bank Section 1Check your understanding of Network layer characteristics by choosing the BEST answer to the following questions. 1. Which OSI layer sends segments to be encapsulated in an IPv4 or IPv6 packet? data link layer network layer transport layer session layer 2. Which layer is responsible for taking an IP packet and preparing it for transmission over the communications medium? physical layer network layer data link layer transport 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? encapsulation fragmentation segmentation serialization 4. Which delivery method does not guarantee that the packet will be delivered fully without errors? connectionless best effort media independent Chapter 6 : Question bank Section 2Check your understanding of the IPv4 packet by choosing the BEST answer to the following questions. 1. 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.) destination IP address protocol Time to Live source IP address Differentiated Services (DS) 2. Which statement is correct about IPv4 packet header fields? The source and destination IPv4 addresses remain the same while travelling from source to destination. The Time to Live field is used to determine the priority of each packet. The Total Length and Header Checksum fields are used to reorder a fragmented packet. The Version field identifies the next level protocol. 3. Which field is used to detect corruption in the IPv4 header? Header Checksum Time to Live Protocol Differentiated Services (DS) 4. Which field includes common values such as ICMP (1), TCP (6), and UDP (17)? Header Checksum Time to Live Protocol Differentiated Services (DS) Chapter 6 : Question bank Section 3Check your understanding of the IPv6 packet by choosing the BEST answer to the following questions. 1. Which three options are major issues associated with IPv4? (Choose three.) IP address depletion increased network complexity and Internet routing table expansion always on connections lack of end-to-end connectivity global and political boundaries too many IPv4 addresses available 2. Which two options are improvements provided by IPv6 as compared to IPv4? (Choose two.) header supports additional fields for complex packets increased the IP address space standardizes the use of NAT supports class-based networks uses a simpler header to provide improved packet handling 3. Which is true of the IPv6 header? it consists of 20 octets. it consists of 40 octets. it contains 8 header fields. it contains 12 header fields. 4. Which is true of the IPv6 packet header? The Hop Limit field replaces the IPv4 Time to Live field. The Source and Destination IPv6 addresses change while travelling from source to destination. The Time to Live field replaces the DiffServ field. The Version field identifies the next header. Chapter 6 : Question bank Section 4Check your understanding of how a host routes by choosing the BEST answer to the following questions. 1. Which statement about host forwarding decisions is true? A host cannot ping itself. A remote destination host is on the same local network as the sending host. Local hosts can reach each other without the need of a router. Routing is enabled on switches to discover the best path to a destination. 2. Which default gateway statement is true? A default gateway is required to send packets to other hosts on the local network. The default gateway address is the IP address of a switch on a remote network. The default gateway address is the IP address of the router on the local network. Traffic can only be forwarded outside the local network if there is no default gateway. 3. Which two commands could be entered on a Windows host to view its IPv4 and IPv6 routing table? (Choose two.) netroute -l netstat -r print route route print print net Chapter 6 : Question bank Section 5Check your understanding of the introduction to routing by choosing the BEST answer to the following questions. 1. What is the command used on a Cisco IOS router to view the routing table? netstart -r route print show ip route show routing table 2. What does a code of “O” indicate next to a route in the routing table? a directly connected route a route with an administrative distance of 0 a gateway of last resort a route learned dynamically from OSPF 3. This type of route is also known as a gateway of last resort. static route remote route default route directly connected route 4. Which is a characteristic of static routes? They are manually configured. They are advertised to directly connected neighbors. They are appropriate when there are many redundant links. They automatically adjust to a change in network topology. 5. True or False? A router can be configured with a combination of both static routes and a dynamic routing protocol. True False Chapter 6 : Sheet Which command can be used on a Windows host to display the routing table? show ip route tracert netstat –r netstat –s 2. What information is added during encapsulation at OSI Layer 3? source and destination MAC source and destination IP address source and destination application protocol source and destination port number 3. How does the network layer use the MTU value? The MTU is passed to the network layer by the data link layer. The network layer depends on the data link layer to set the MTU, and adjusts the speed of transmission to accommodate it. To increase speed of delivery, the network layer ignores the MTU. The network layer depends on the higher level layers to determine the MTU. 4. Which characteristic describes an IPv6 enhancement over IPv4? Both IPv4 and IPv6 support authentication, but only IPv6 supports privacy capabilities. The IPv6 address space is four times bigger than the IPv4 address space. The IPv6 header is simpler than the IPv4 header is, which improves packet handling. IPv6 addresses are based on 128-bit flat addressing as opposed to IPv4 which is based on 32-bit hierarchical addressing. 5. Which statement accurately describes a characteristic of IPv4? IPv4 natively supports IPsec. All IPv4 addresses are assignable to hosts. IPv4 has a 32-bit address space. An IPv4 header has fewer fields than an IPv6 header has. 6. When a router receives a packet, what information must be examined in order for the packet to be forwarded to a remote destination? source MAC address destination IP address destination MAC address source IP address 7. A computer has to send a packet to a destination host in the same LAN. How will the packet be sent? 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. The packet will be sent directly to the destination host. 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. The packet will be sent only to the default gateway. 8. Which IPv4 address can a host use to ping the loopback interface? 127.0.0.1 126.0.0.1 126.0.0.0 127.0.0.0 9. When a connectionless protocol is in use at a lower layer of the OSI model, how is missing data detected and retransmitted if necessary? The best-effort delivery process guarantees that all packets that are sent are received. Network layer IP protocols manage the communication sessions if connection-oriented transport services are not available. Connectionless acknowledgements are used to request retransmission. Upper-layer connection-oriented protocols keep track of the data received and can request retransmission from the upper-level protocols on the sending host. 10. What was the reason for the creation and implementation of IPv6? to relieve IPv4 address depletion to provide more address space in the Internet Names Registry to make reading a 32-bit address easier to allow NAT support for private addressing 11. Which information is used by routers to forward a data packet toward its destination? destination data-link address source data-link address source IP address destination IP address 12. Which field in an IPv4 packet header will typically stay the same during its transmission? Time-to-Live Destination Address Packet Length Flag 13. Which field in an IPv6 packet is used by the router to determine if a packet has expired and should be dropped? No Route to Destination Hop Limit Address Unreachable TTL