Networking Basics - Chap 8 - 10
What important information is examined in the Ethernet frame header by a Layer 2 device in order to forward the data onward?
destination MAC address
Which term describes a field in the IPv4 packet header that contains an 8-bit binary value used to determine the priority of each packet?
differentiated services
What is one advantage that the IPv6 simplified header offers over IPv4?
efficient packet handling
When transporting data from real-time applications, such as streaming audio and video, which field in the IPv6 header can be used to inform the routers and switches to maintain the same path for the packets in the same conversation?
flow label
. Within a production network, what is the purpose of configuring a switch with a default gateway address?
forwards packets from the switch to remote networks
Under which two circumstances will a switch flood a frame out of every port except the port that the frame was received on?
frame has broadcast address as destination destination address is unknown to switch
Which parameter does the router use to choose the path to the destination when there are multiple routes available?
lower metric value associated with destination network
Which two types of IPv6 messages are used in place of ARP for address resolution?
neighbor solicitation and advertisement
What IPv4 header field identifies the upper layer protocol carried in the packet?
protocol
What routing table entry has a next hop address associated with a destination network?
remote routes
What are two services provided by the OSI network layer?
routing packets to the destination encapsulating PDUs from transport layer
What are two potential network problems that can result from ARP operation?
- Hackers can use MAC and IP addresses in ARP to intercept network traffic - Cause delays in communication data
Which IPv4 address can a host use to ping the loopback interface?
127.0.0.1
Where are IPv4 address to Layer 2 Ethernet address mappings maintained on a host computer?
ARP cache
A network technician issues the arp -d * command on a PC after the router that is connected to the LAN is reconfigured. What is the result after this command is issued?
ARP cache is cleared
What statement describes the function of the Address Resolution Protocol?
ARP is used to discover MAC address of any host on local network
Why is NAT not needed in IPv6?
Any host can get a public IPV6 address cause they're extremely large
What happens when the transport input ssh command is entered on the switch vty lines?
Communication is encrypted
A router boots and enters setup mode. What is the reason for this?
Config file is missing from NVRAM
Which information is used by routers to forward a data packet toward its destination?
Destination IP Address
Which term describes a field in the IPv4 packet header that contains a unicast, multicast, or broadcast address?
Destination IPV4 address
What property of ARP causes the request to be flooded out all ports of a switch except for the port receiving the ARP request?
Destination MAC address FF-FF... appears in ethernet frame header
What property of ARP forces all Ethernet NICs to process an ARP request?
Destination MAC address FF-FF... appears in ethernet frame header
What property of ARP causes cached IP-to-MAC mappings to remain in memory longer?
Entries are time-stamped and purged when timeout expires
A new network administrator has been asked to enter a banner message on a Cisco device. What is the fastest way a network administrator could test whether the banner is properly configured?
Exit priviledged exec mode and press enter
Which destination address is used in an ARP request frame?
FFFF.FFFF.FFFF
A computer has to send a packet to a destination host in the same LAN. How will the packet be sent?
Packet will be sent directly to destination host
Which term describes a field in the IPv4 packet header used to detect corruption in the IPv4 header?
Header checksum
What will happen if the default gateway address is incorrectly configured on a host?
Host cannot communicate with other hosts on other network
Which statement describes a feature of the IP protocol?
IP relies on upper layer services to handle missing or out-of-order packets
Which three commands are used to set up secure access to a router through a connection to the console interface?
Line console 0 Login Password cisco
What property of ARP allows hosts on a LAN to send traffic to remote networks?
Local hosts learn MAC address of default gateway
What is the effect of using the Router# copy running-config startup-config command on a router?
NVRAM contents will change
Which two functions are primary functions of a router?
Packet forwarding and path selection
Which term describes a field in the IPv4 packet header that contains a 32-bit binary value associated with an interface on the sending device?
Source IPV4 address
What property of ARP causes a reply only to the source sending an ARP request?
Source MAC address appears in ethernet frame header
What property of ARP allows MAC addresses of frequently used servers to be fixed in the ARP table?
Static IP to MAC addresses can be entered manually
Which term describes a field in the IPv4 packet header used to limit the lifetime of a packet?
TTL (time to live)
What property of ARP causes the NICs receiving an ARP request to pass the data portion of the Ethernet frame to the ARP process?
The type field 0x806 appears in the header of the Ethernet frame.
Which field in the IPv4 header is used to prevent a packet from traversing a network endlessly?
Time to live
Which term describes a field in the IPv4 packet header that contains a 4-bit binary value set to 0100?
Version
A computer can access devices on the same network but cannot access devices on other networks. What is the probable cause of this problem?
computer has invalid default gateway
What is a basic characteristic of the IP protocol?
connectionless
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?
create a new layer 2 ethernet frame to send to destination
How do hosts ensure that their packets are directed to the correct network destination?
routing tables
What are two functions of NVRAM?
save contents when power is removed store startup config files
The global configuration command ip default-gateway 172.16.100.1 is applied to a switch. What is the effect of this command?
switch can be managed remotely from a host on another network
What is the aim of an ARP spoofing attack?
to associate IPs to the wrong MAC addresses
What information does the loopback test provide?
whether the TCP/IP stack is working properly
