Chapter 8: Network Layer

Which field is used to detect corruption in the IPv4 header? Header Checksum Time to Live Protocol Differentiated Services (DS)

Header Checksum

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.

it consists of 40 octets. it contains 8 header fields

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

show ip route

What information is added during encapsulation at OSI Layer 3? source and destination MAC source and destination port number source and destination IP address source and destination application protocol

source and destination IP address

What was the reason for the creation and implementation of IPv6? to allow NAT support for private addressing to make reading a 32-bit address easier to relieve IPv4 address depletion to provide more address space in the internet Names Registry.

to relieve IPv4 address depletion

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

127.0.0.1

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

Data Link Layer

Which field in an IPv4 packet header will typically stay the same during its transmission? Time-to-Live Destination Address Flag Packet Length

Destination Address

Which information is used by routers to forward a data packet toward its destination? Destination IP address Source IP address Source data-link address Destination data-link address

Destination IP address

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 segmenttation serialization

Fragmentation

Which field in an IPv6 packet is used by the router to determine if a packet has expired and should be dropped? TTL No Route to Destination Address Unreachable Hop Limit

Hop Limit

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

IP address depletion Increased network complexity and internet routing table expansion. lack of end-to-end connectivity

Which statement accurately describes a characteristic of IPv4? All IPv4 addresses are assignable to hosts. All IPv4 header has fewer fields than an IPv6 header has. IPv4 natively supports IPsec. IPv4 has a 32-bit address space.

IPv4 has a 32-bit address space.

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

Increased the IP address space Uses a simpler header to provide improved packet handling

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.

Local hosts can reach each other without the need of a router.

Which OSI layer sends segments to be encapsulated in an IPv4 or IPv6 packet? Data Link Layer Network Layer Transport Layer Session Layer

Network Layer

Which field includes common values such as ICMP (1), TCP (6), and UDP (17)? Header Checksum Time to Live Protocol Differentiated Services (DS)

Protocol

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 traveling from source to destination. The Time to Live field replaces the DiffServ field. The Version field identifies the next header.

The Hop Limit field replaces the IPv4 Time to Live field

Which characteristic describes an IPv6 enhancement over IPv4? The IPv6 header is simpler than the IPv4 header is, which improves packet handling. IPv6 address space is four times bigger than the IPv4 address space. IPv6 addresses are based on 128-bit flat addressing as opposed to IPv4 which is based on 32-bit hierarchical addressing. Both IPv4 and IPv6 support authentication, but only IPv6 supports privacy capabilities.

The IPv6 header is simpler than the IPv4 header is, which improves packet handling.

How does the network layer use the MTU value?

The MTU is passed to the network layer by the data link layer

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.

The default gateway address is the IP address of the router on the local network.

A computer has to send a packet to a destination host in the same LAN. How will the packet be sent? The packet will be sent only to the default gateway. 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 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 directly to the destination host.

Which statement is correct about IPv4 packet header fields? The source and destination IPv4 addresses remain the same while traveling 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.

The source and destination IPv4 addresses remain the same while traveling from source to destination.

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.

They are manually configured.

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

True

When a connection-less protocol is in use at a lower layer of the OSI model, how is missing data detected and re-transmitted if necessary? Upper-layer connection-oriented protocols keep track of the data received and can request retransmission from the upper-level protocols on the sending host. The best-effort delivery process guarantees that all packets that are sent are received. Connection-less acknowledgements are used to request re-transmission Network layer IP protocols manage the communication sessions if connection-oriented transport services are not available.

Upper-layer connection-oriented protocols keep track of the data received and can request retransmission from the upper-level protocols on the sending host.

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

a route learned dynamically from OSPF

Which delivery method does not guarantee that the packet will be delivered fully without errors? connectionless best effort media independent

best effort

This type of route is also known as a gateway of last resort. default route static route remote route directly connected route

default route

Which two commands could be entered on a Windows host to view its IPv4 and IPv6 routing table? (Choose two.) netroute -I netstat -r print route route print print net

netstat -r route print

When a router receives a packet, what information must be examined in order for the packet to be forwarded to a remote destination? destination IP address destination MAC address source MAC address source IP address

destination IP address

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)

destination IP address Source IP address