8.6.2 Network Layer

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

a-netstat -s

b-show ip route

c-netstat -r

d-tracert

netstat -r

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

a-source and destination MAC

b-source and destination application protocol

c-source and destination port number

d-source and destination IP address

source and destination IP address

How does the network layer use the MTU value?

a-The network layer depends on the higher level layers to determine the MTU.

b-The network layer depends on the data link layer to set the MTU, and adjusts the speed of transmission to accommodate it.

c-The MTU is passed to the network layer by the data link layer.

d-To increase speed of delivery, the network layer ignores the MTU.

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

Which characteristic describes an IPv6 enhancement over IPv4?

a-IPv6 addresses are based on 128-bit flat addressing as opposed to IPv4 which is based on 32-bit hierarchical addressing.

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

c-Both IPv4 and IPv6 support authentication, but only IPv6 supports privacy capabilities.

d-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.

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-Connectionless acknowledgements are used to request retransmission.

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

c-Network layer IP protocols manage the communication sessions if connection-oriented transport services are not available.

d-The best-effort delivery process guarantees that all packets that are sent are received.

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

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

a-to make reading a 32-bit address easier

b-to relieve IPv4 address depletion

c-to provide more address space in the Internet Names Registry

d-to allow NAT support for private addressing

to relieve IPv4 address depletion

Which statement accurately describes a characteristic of IPv4?

a-All IPv4 addresses are assignable to hosts.

b-IPv4 has a 32-bit address space.

c-An IPv4 header has fewer fields than an IPv6 header has.

d-IPv4 natively supports IPsec.

IPv4 has a 32-bit address space.

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

a-Flag

b-Time-to-Live

c-Packet Length

d-Destination Address

Destination Address

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 MAC address

b-source IP address

c-destination IP address

d-source MAC address

c-destination IP address

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

a-TTL

b-Hop Limit

c-Address Unreachable

d-No Route to Destination

Hop Limit

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

source IP address

destination IP address

source data-link address

destination data-link address

destination IP address

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 first be sent to the default gateway, and then from the default gateway it will be sent directly to the destination host.

d-The packet will be sent only to the default gateway.

The packet will be sent directly to the destination host.

A router receives a packet from the Gigabit 0/0 interface and determines that the packet needs to be forwarded out the Gigabit 0/1 interface. What will the router do next?

a-route the packet out the Gigabit 0/1 interface

b-create a new Layer 2 Ethernet frame to be sent to the destination

c-look into the ARP cache to determine the destination IP address

d-look into the routing table to determine if the destination network is in the routing table

create a new Layer 2 Ethernet frame to be sent to the destination

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

a-126.0.0.1

b-127.0.0.0

c-126.0.0.0

d-127.0.0.1

127.0.0.1