問題一覧
1
When a connectionless protocol is in use at a lower layer of the OSI model, how is missing data detected and retransmitted 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.
2
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
3
What is one function of the ARP protocol?
resolving an IPv4 address to a MAC address
4
In NAT translation for internal hosts, what address would be used by external users to reach internal hosts?
inside global
5
Which two ICMPv6 messages are used during the Ethernet MAC address resolution process? (Choose two.)
neighbor solicitation, neighbor advertisement
6
What type of server would use IMAP?
7
Which field in an IPv6 packet is used by the router to determine if a packet has expired and should be dropped?
Hop Limit
8
Which information is used by routers to forward a data packet toward its destination?
destination IP address
9
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.
10
Which two basic functions that ARP provides?
Resolving IPv4 addresses to MAC addresses, Maintaining an ARP table of IPv4 to MAC address mappings
11
Refer to the Figure 1 below. NAT is configured on Remote and Main. The PC is sending a request to the web server. What IPv4 address is the source IP address in the packet between Main and the web server?
203.0.113.5
12
A particular website does not appear to be responding on a Windows 7 computer. What command could the technician use to show any cached DNS entries for this web page?
ipconfig /displaydns
13
Which destination address is used in an ARP request frame?
FFFF.FFFF.FFFF
14
What information is added during encapsulation at OSI Layer 3?
source and destination IP address
15
Which field in an IPv4 packet header will typically stay the same during its transmission?
Destination Address
16
Which characteristic describes an IPv6 enhancement over IPv4?
The IPv6 header is simpler than the IPv4 header is, which improves packet handling.
17
Which statement accurately describes a characteristic of IPv4?
IPv4 has a 32-bit address space.
18
What is the benefit of using DDNS?
The DDNS provider detects a change to the client IP address and immediately updates the mapping change.
19
Which protocol enables mail to be downloaded from an email server to a client and then deletes the email from the server?
POP3
20
What addresses are mapped by ARP?
destination MAC address to a destination IPv4 address
21
What was the reason for the creation and implementation of IPv6?
b. to relieve IPv4 address depletion
22
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 be sent to the destination
23
Which command can be used on a Windows host to display the routing table?
netstat -r
24
Which message does an IPv4 host use to reply when it receives a DHCPOFFER message from a DHCP server?
DHCPREQUEST
25
Which action is taken by a Layer 2 switch when it receives a Layer 2 broadcast frame?
It sends the frame to all ports except the port on which it received the frame.
26
Which router component holds the routing table, ARP cache, and running configuration file?
RAM
27
A PC is configured to obtain an IP address automatically from network 192.168.1.0/24. The network administrator issues the arp –a command and notices an entry of 192.168.1.255 ff-ff-ff-ff-ff-ff. Which statement describes this entry?
This is a static map entry.
28
What type of information is contained in an ARP table?
IP address to MAC address mappings
29
The ARP table in a switch maps which two types of address together?
Layer 3 address to a Layer 2 address
30
Which application layer protocol uses message types such as GET, PUT, and POST?
HTTP
31
A computer can access devices on the same network but cannot access devices on other networks. What is the probable cause of this problem?
The computer has an invalid default gateway address.
32
What application layer protocol describes the services that are used for file sharing in Microsoft networks?
SMB
33
On a home network, which device is most likely to provide dynamic IP addressing to clients on the home network?
a home router
34
Which statement best describes the operation of the File Transfer Protocol?
An FTP server uses a source port number of 21 and a randomly generated destination port number during the establishment of control traffic with an FTP client.
35
What will a Layer 2 switch do when the destination MAC address of a received frame is not in the MAC table?
It forwards the frame out of all ports except for the port at which the frame was received.
36
A cybersecurity analyst believes an attacker is spoofing the MAC address of the default gateway to perform a man-in-themiddle attack. Which command should the analyst use to view the MAC address a host is using to reach the default gateway?
arp -a
37
How does the ARP process use an IP address?
to determine the MAC address of a device on the same network
38
Which website is considered secure because it encrypts the communication between the website and visitors?
https://www.ourblogs.info/
39
What is an example of a top-level domain?
cisco.com
40
Which protocol automates assignment of IP addresses on a network, and which port number does it use? (Choose two.)
67, DHCP
41
When an IP packet is sent to a host on a remote network, what information is provided by ARP?
the MAC address of the router interface closest to the sending host
42
How does the network layer use the MTU value?
The MTU is passed to the network layer by the data link layer.
43
What is the purpose of ARP in an IPv4 network
to obtain a specific MAC address when an IP address is known
44
What is the function of ARP?
resolving IPv4 addresses to MAC addresses
45
Which IPv4 address can a host use to ping the loopback interface?
127.0.0.1