Where does routing occur within the DoD TCP/IP reference model?
A. application B. internet C. network D. transport
Answer: B Explanation:
The picture below shows the comparison between TCP/IP model & OSI model. Notice that
the Internet Layer of TCP/IP is equivalent to the Network Layer which is responsible for
routing decision.
Jimmy is correct Apr 3, 2018
Internet its the correct answer Mar 15, 2018
b Oct 27, 2017
internet Oct 27, 2017
B INTERNET
it my ansser ok
Oct 24, 2017
b Oct 16, 2017
C. Internet Layer Sep 15, 2017
internet Sep 7, 2017
B internet layer Sep 2, 2017
C Network Layer Aug 31, 2017
internet corresponds to the Network layer in the OSI Model Aug 30, 2017
Internet layer Aug 30, 2017
A. application
Aug 29, 2017
internet layer of tcp/ip is equivalent to network layer of the OSI model Aug 29, 2017
Esta pregunta sale en el examen Aug 29, 2017
in my point of view the answer is D Aug 21, 2017
In fact, Routing takes place in "Network Layer" in OSI Reference Model which is "Internet Layer' in DoD TCP/IP Reference Model. Aug 16, 2017
Jimmy is Absolutely correct Aug 15, 2017
Answer should be B Aug 15, 2017
C- network layer Aug 9, 2017
b- internet
TCP/IP model before OSI model Aug 6, 2017
wrong. It is the internet Aug 5, 2017
I want to know where does routing occurs whitin the DoD OSI reference model Aug 2, 2017
B. Internet layer Aug 2, 2017
B internet layer Jul 31, 2017
Occur on C. network Jul 25, 2017
B Network Layer Jul 17, 2017
The answer is B Reason: This question is asking about the TCP/IP model, not the OSI model. OSI is Network, TCP/IP calls it Internet. Jul 16, 2017
B Internet layer within the TCP/IP model. Jul 15, 2017
internet layer
Jul 5, 2017
B. Internet layer Jul 4, 2017
B Internet is equal to network layer at OSI where routing occurs Jul 3, 2017
B internet layer Jun 29, 2017
the answer is b Jun 29, 2017
C internet layer Jun 28, 2017
B - Internet layer in TCP MODEL Jun 26, 2017
B is the right answer Jun 23, 2017
B. internet Jun 19, 2017
internet layer Jun 7, 2017
B internet layer Jun 2, 2017
C. network layer
May 31, 2017
occur in the Internet layer May 13, 2017
The routing occur in the Internet layer. May 13, 2017
May 13, 2017
Internet Layer of TCP/IP is equivalent to the Network Layer which is responsible for routing decision. May 11, 2017
In the TCP/IP model the routing occur in the Internet layer May 4, 2017
C Network layer May 2, 2017
Question No : 2 - Topic 1
Which of the following statements describe the network shown in the graphic? (Choose
two.)
A. There are two broadcast domains in the network. B. There are four broadcast domains in the network. C. There are six broadcast domains in the network. D. There are four collision domains in the network. E. There are five collision domains in the network. F. There are seven collision domains in the network.
Answer: A,F Explanation:
Only router can break up broadcast domains so in the exhibit there are 2 broadcast
domains: from e0 interface to the left is a broadcast domain and from e1 interface to the
right is another broadcast domain ->.
Both router and switch can break up collision domains so there is only 1 collision domain
on the left of the router (because hub doesnt break up collision domain) and there are 6
collision domains on the right of the router (1 collision domain from e1 interface to the
switch + 5 collision domains for 5 PCs in Production) ->.
* hub acts as single broadcast domain and single collision domain ,so it doesn't matter have many ports it include
* switch by default having one broadcast domain and port per collision domain it means one port = one collision domain
* in router port per broadcast domain
in that fig shows us
router with two ports e0 and e1 this two ports are different broadcast domains and e0 port connected to the hub so that entire
connectivity comes under single broadcast domain and collision domain because of the hub nature .
e1 interface connected to the switch port " e1 to switch connected interface comes under one collision domain and 5 individual pc's
and individual collision domains and
so there totally two broadcast domains and seven collision domains
Feb 1, 2018
A. There are two broadcast domains in the network and F. There are seven collision domains in the network Oct 24, 2017
A&F. There are two broadcast domains in the network, There are seven collision domains in the network. Sep 15, 2017
Each port of the switch is a collision domain and the hub only have 1 collision domain, So they are 6 ports on the switch which make it 6 collisions on the switch side and 1 on the hub side. Absolutely correct
Aug 29, 2017
Answer to my recollection should be A and F Aug 15, 2017
A and f are the correct Aug 9, 2017
two broadcast domains and 7 collision domain Aug 2, 2017
A n F Jul 31, 2017
A. There are two broadcast domains in the network
F. There are seven collision domains in the network.
Jul 25, 2017
A. There are two broadcast domains in the network. There are seven collision domains in the network. Jul 25, 2017
A. There are two broadcast domains in the network
F. There are seven collision domains in the network. Jul 19, 2017
two broadcast domains and 7 collision domains Jul 5, 2017
A & F. There are two broadcast domain if no VLANs are confiigured on the switch and seven collision domains. Jul 4, 2017
A two broadcast domains Jul 3, 2017
There are two broadcast domains in the network and there are seven collision domains in the network Jun 28, 2017
A AND F both are correct Jun 23, 2017
The line A and D describes very well what we have there. Two broadcast domains and four colision domains. Jun 22, 2017
Hosts in Sales side are connected on a Hub which always works as a single Broadcast and collision domain, no matter how many devices are connected or how many ports it has.
On the Production side Hosts are connected to a switch, which works as a single broadcast domain by default as all ports are participating in VLAN1 and each ports are separate collision domains by design.
As per the diagram there are 5 hosts and a router connected to the switch. So in total there are 2 Broadcast domains and 7 Collision domains.
Jun 11, 2017
A ther are two brodcast domains in the network May 31, 2017
didnt catch that that was a hub :( May 29, 2017
May 23, 2017
A There are two broadcast domains in the network
May 18, 2017
Trick question: there is a HUB on the left, and a SWITCH on the right. There look sufficiently alike that you would think they are both switches if you AREN'T CAREFUL! May 15, 2017
I'm a bit lost on this one. There are only three collision domains in this picture. The hub on the left makes for one whole collision domain for the right side (as mentioned in the picture). There is then one collision domain between the router on the switch on the right. And then all five computers are somehow connected to a single cable coming into the switch, making for one collision domain for all five of those PCs as well. The collision is on the wire, not on the device. So one wire leaving the switch means one collision domain. May 11, 2017
There are two broadcast domains in the network. There are seven collision domains in the network May 4, 2017
Question No : 3 - Topic 1
A network interface port has collision detection and carrier sensing enabled on a shared
twisted pair network. From this statement, what is known about the network interface port?
A. This is a 10 Mb/s switch port. B. This is a 100 Mb/s switch port. C. This is an Ethernet port operating at half duplex. D. This is an Ethernet port operating at full duplex. E. This is a port on a network interface card in a PC.
Answer: C Explanation:
Modern Ethernet networks built with switches and full-duplex connections no longer utilize
CSMA/CD. CSMA/CD is only used in obsolete shared media Ethernet (which uses repeater
or hub).
C: This is an Ethernet port operating at half duplex. Mar 13, 2018
C Nov 1, 2017
C IS THE CORRECT ANS Sep 4, 2017
This is a 10Mb/s switch port, operating in half duplex.
A, C Aug 1, 2017
C Jul 31, 2017
D. This is an Ethernet port operating at full duplex. Jul 25, 2017
C. This is an Ethernet port operating at half duplex. Jul 19, 2017
C. This is an Ethernet port operating at half duplex. Jul 19, 2017
C. Operating at Half-Duplex Jul 15, 2017
This is an Ethernet port operating at half duplex.
Jul 5, 2017
D. This is an Ethernet port operating at full duplex Jul 4, 2017
this port is operated half duplex Jun 28, 2017
This is an Ethernet port operating at half duplex. May 13, 2017
Question No : 4 - Topic 1
Host 1 is trying to communicate with Host 2. The e0 interface on Router C is down.
Which of the following are true? (Choose two.)
A. Router C will use ICMP to inform Host 1 that Host 2 cannot be reached. B. Router C will use ICMP to inform Router B that Host 2 cannot be reached. C. Router C will use ICMP to inform Host 1, Router A, and Router B that Host 2 cannot be reached. D. Router C will send a Destination Unreachable message type. E. Router C will send a Router Selection message type. F. Router C will send a Source Quench message type.
Answer: A,D Explanation:
Host 1 is trying to communicate with Host 2. The e0 interface on Router C is down. Router
C will send ICMP packets to inform Host 1 that Host 2 cannot be reached.
ICMP is always used to communicate errors and other messages regarding network and host availability. ICMP has many more uses than just PING or Traceroute Mar 8, 2018
A&D Router C will use ICMP to inform Host 1 that Host 2 cannot be reached.
Router C will send a Destination Unreachable message type. Sep 15, 2017
I think the question misleading. Although it state that "Host 1 is trying to communicate with Host 2", it did not state if it is icmp, tcp or udp. Naturally Host 1 will not send ICMP packets without triggering ping command of sort. Thus to say that router C will reply to Host 1 via icmp is misleading. But since it state that there is two answers, A and C is the best out of the 6. Aug 27, 2017
D and A Jul 31, 2017
A. Router C will use ICMP to inform Host 1 that Host 2 cannot be reached.
D. Router C will send a Destination Unreachable message type. Jul 19, 2017
Router C will use ICMP to inform Host 1 that Host 2 cannot be reached Jun 28, 2017
Router C will inform host 1 that host 2 cannot be reached.
Router C will send a Destination Unreachable Message Type Jun 14, 2017
Host 1 is trying to communicate with Host 2. Its packets travel from routerA to routerB and router C. Router C (the last router) then broadcast an ARP frame onto the network looking for the MAC address of Host 2. If Host 2 can answer then router C can forward the frame. But e0 interface is down so no answer from Host 2 will be received so router C will send a Destination Unreachable message back to the originator. This message also informs that the middle network is still working correctly.
Also notice that the Destination Unreachable message is an ICMP message. Jun 8, 2017
The answer is c Jun 6, 2017
Interface is down but Router C is on. It tests e0 interface and advise about its status. May 31, 2017
What confuses me here is how can router C send ICMP packets back if the interface is down? May 24, 2017
C. Router C will use ICMP to inform Host 1, Router A, and Router B that Host 2 cannot be reached. May 19, 2017
Router C will use ICMP to inform Host 1 that Host 2 cannot be reached. Router C will send a Destination Unreachable message type May 18, 2017
Router C will use ICMP to inform Router B that Host 2 cannot be reached and will send a Unreachable message type May 13, 2017
C. Router C will use ICMP to inform Host 1, Router A, and Router B that Host 2 cannot be reached. May 10, 2017
Question No : 5 - Topic 1
Refer to the exhibit.
Based on the information given, which switch will be elected root bridge and why?
A. Switch A, because it has the lowest MAC address B. Switch A, because it is the most centrally located switch C. Switch B, because it has the highest MAC address D. Switch C, because it is the most centrally located switch E. Switch C, because it has the lowest priority F. Switch D, because it has the highest priority
Answer: E Explanation:
To elect the root bridge in the LAN, first check the priority value. The switch having the
lowest priority will win the election process. If Priority Value is the same then it checks the
MAC Address; the switch having the lowest MAC Address will become the root bridge. In
this case, switch C has the lowest MAC Address so it becomes the root bridge.
D. Switch C, because it is the most centrally located switch Oct 24, 2017
That would be true for PVST since it adds the VLAN number to the set priority, however with MST is will show a 0. Oct 13, 2017
Can you set the priority to 1? I think it has to be from 0 to 61440 in increments of 4096. So, 0 4096 8192 etc. IS this the Prio.Nbr., ie. 128.1? Oct 13, 2017
please can I use this material to study for my exam? Oct 11, 2017
c Oct 1, 2017
It is true that you cannot give the command with priority 1, but it you give the priority 0, then on show spanning-tree command it will show that it is priority 1. So the correct answer is E. Sep 30, 2017
bravo........
Sep 18, 2017
Sorry you all have the wrong answer. The answer should be A the lowest Mac address it cannot be E as you can not have a priority of 1 it has to be 0 or increments of 4096
Sep 6, 2017
E. Lowest priority always gets elected as root bridge
Sep 4, 2017
kindly help me understand how you get the lowest mac addresses. Aug 3, 2017
Switch C will be the root bridge
E Aug 1, 2017
Switch C because it has the lowest priority Jul 31, 2017
I understand Lowest Priority is the answer, however if Priority is the same, you would choose the lowest mac address. Sw-C has the highest mac add(E is greater than D), is there something i'm not understanding about the second part of the answer?? It states C would still be the root bridge based on macs. Jul 19, 2017
E switch C, because it has the lowest priority Jun 28, 2017
Switch C, because it has the lowest priority. You always want to make sure that you check the priority before anything else. If the priority matches that of another switch, you will then look at the switch with the lower MAC address which will then define the elected root bridge. The answer is E. Jun 14, 2017
Switch C has the lowest priority of 1 so it is elected as the root bridge Jun 12, 2017
E. Switch C, because it has the lowest priority May 13, 2017
The mac address is not evaluate Since having lower priority no longer matters the value of the mac address May 4, 2017
switch has the lowest priority 1,
May 2, 2017
Answer E is correct and I follow your explanation regarding Priority. In the second case where Priority is the same, I think the last sentence should say, "In this case, switch A has the lowest MAC Address so it becomes the root bridge." Apr 23, 2017
Question No : 6 - Topic 1
Which layer in the OSI reference model is responsible for determining the availability of the
receiving program and checking to see if enough resources exist for that communication?
A. transport B. network C. presentation D. session E. application
Answer: E Explanation:
This question is to examine the OSI reference model.
The Application layer is responsible for identifying and establishing the availability of the
intended communication partner and determining whether sufficient resources for the
intended communication exist.
The Correct Answer is E. Sep 29, 2017
application layer
Aug 29, 2017
E. Application layer Aug 1, 2017
Application layer Jul 31, 2017
E Application
Jul 21, 2017
D session layer Jun 28, 2017
E. application May 13, 2017
That is a correct answer May 11, 2017
Question No : 7 - Topic 1
Refer to the graphic.
Host A is communicating with the server. What will be the source MAC address of the
frames received by Host A from the server?
A. the MAC address of router interface e0 B. the MAC address of router interface e1 C. the MAC address of the server network interface D. the MAC address of host A
Answer: A Explanation:
Whereas switches can only examine and forward packets based on the contents of the
MAC header, routers can look further into the packet to discover the network for which a
packet is destined. Routers make forwarding decisions based on the packet's network-
layer header (such as an IPX header or IP header). These network-layer headers contain
source and destination network addresses. Local devices address packets to the router's
MAC address in the MAC header. After receiving the packets, the router must perform the
following steps:
1. Check the incoming packet for corruption, and remove the MAC header. The router
checks the packet for MAC-layer errors. The router then strips off the MAC header and
examines the network-layer header to determine what to do with the packet.
2. Examine the age of the packet. The router must ensure that the packet has not come too
far to be forwarded. For example, IPX headers contain a hop count. By default, 15 hops is
the maximum number of hops (or routers) that a packet can cross. If a packet has a hop
count of 15, the router discards the packet. IP headers contain a Time to Live (TTL) value.
Unlike the IPX hop count, which increments as the packet is forwarded through each
router, the IP TTL value decrements as the IP packet is forwarded through each router. If
an IP packet has a TTL value of 1, the router discards the packet. A router cannot
decrement the TTL value to 1 and then forward the packet.
3. Determine the route to the destination. Routers maintain a routing table that lists
available networks, the direction to the desired network (the outgoing interface number),
and the distance to those networks. After determining which direction to forward the packet,
the router must build a new header. (If you want to read the IP routing tables on a Windows
95/98 workstation, type ROUTE PRINT in the DOS box.)
4. Build the new MAC header and forward the packet. Finally, the router builds a new MAC
header for the packet. The MA
nope, just verified it in packet tracer, the MAC address is of the port from where the packet is leaving i.e. E0
Nov 19, 2017
the question is regarding the source MAC address of the packet sent by the server to host A. the IP address of the packet does not change but the MAC address keep changing from hop to hop. When the packet is sent from server, the source MAC address if of server and destination MAC address is of router E1 interface (as every interface of router has different MAC address.) Now the router will remove the MAC addresses and replace the source MAC address to it's E0 interface MAC address and destination MAC address to Host A MAC address Nov 19, 2017
also confirmed with packet capture, it's E1 Sep 20, 2017
Can someone please explain further why the answer to this question is option A, i'm not sure i understand the explanation. Sep 15, 2017
A. the MAC address of router interface e0 Aug 6, 2017
A. The mac address of Router e0 interface. Aug 1, 2017
mac address of router interface e0 Jul 31, 2017
A. the MAC address of router interface e0 Jul 25, 2017
Incorrect. It has the router egress interface - e1. Double-checked it with packet sniffing. Jul 25, 2017
A the MAC address of router interface e0 Jun 28, 2017
A.the MAC address of router interface e0 Jun 23, 2017
the MAC address of router interface e0 May 13, 2017
Question No : 8 - Topic 1
A router has two Fast Ethernet interfaces and needs to connect to four VLANs in the local
network. How can you accomplish this task, using the fewest physical interfaces and
without decreasing network performance?
A. Use a hub to connect the four VLANS with a Fast Ethernet interface on the router. B. Add a second router to handle the VLAN traffic. C. Add two more Fast Ethernet interfaces. D. Implement a router-on-a-stick configuration.
Answer: D Explanation:
A router on a stick allows you to use sub-interfaces to create multiple logical networks on a
single physical interface.
D. Implement a router-on-a-stick configuration. Aug 6, 2017
D. Implement a router-on-a-stick configuration Aug 1, 2017
implement a router on a stick configuration Jul 31, 2017
D. Implement a router-on-stick configuration Jun 28, 2017
D. Implement a router-on-a-stick configuration. Jun 23, 2017
D. Implement a router-on-a-stick configuration. May 13, 2017
Question No : 9 - Topic 1
Match the terms on the left with the appropriate OSI layer on the right. (Not all options are
used.)
Answer:
networks - packets, IP address, routing - Layer Transport - UDP, segments, windowing. Mar 25, 2018
packets, IP address, routing UDP segments windowing
Aug 30, 2017
Network layer:
Packet
IP address
routing
Transport Layer
Segments
Windowing
UDP Aug 1, 2017
For Network Layer: packets, IP addresses, routing.
FOr Transport Layer: UDP, segments, windowing Jul 1, 2017
I missed windowing :( Jun 28, 2017
Network Layer: packets, ip adresses, routing
Transport layer: UDP, segments, windowing Jun 23, 2017
Network layer==>packets,ip adresses,routing. Transport layer==>segments,windowing,udp May 19, 2017
networks - packets, IP address, routing - Layer Transport - UDP, segments, windowing May 13, 2017
Question No : 10 - Topic 1
A network administrator is verifying the configuration of a newly installed host by
establishing an FTP connection to a remote server. What is the highest layer of the
protocol stack that the network administrator is using for this operation?
A. application B. presentation C. session D. transport E. internet F. data link
Answer: A Explanation:
FTP belongs to Application layer and it is also the highest layer of the OSI model.
FOR FTP THE HIGHEST LAYER IS session Sep 18, 2017
Application layer Sep 13, 2017
A. application Aug 6, 2017
Its the Application layer Aug 1, 2017
Application layer Jul 31, 2017
A. application
Jun 5, 2017
A. application May 13, 2017
Question No : 11 - Topic 1
Refer to the exhibit. Complete this network diagram by dragging the correct device name or
description to the correct location. Not all the names or descriptions will be used.
Answer:
Router, DTE, DCE, Switch, digital line, WAN Service provider network. Mar 25, 2018
router DTE DCE CSU/DSU Digital line WAN Sep 1, 2017
ROUTER---->DTE----->DCE----->CSU/DSU----->DIGITAL LINE------>WAN SERVICE PROVIDER NETWORk Aug 26, 2017
Router, DTE, DCE, CSU/DSU Synchronous, Digital Line, WAN Service Provider Network Aug 22, 2017
Router -> DTE -> DCE -> CSU/DSU Synchrnous -> Digital Line -> WAN Service Provider Network Aug 8, 2017
Router->DTE->DCE->CSU/DSU Synchronous->Digital Line->WAN Service Provider Network Aug 2, 2017
Router, DTE, DCE, CSU/DSU, Digital Line, WAN Service Provider Network Aug 1, 2017
router,DTE,DCE,CSU/DSU synchronous,digital line,Wan service provider network Jul 31, 2017
router,dte,dce,csu/dsu,digital line ,wan service provider network Jul 24, 2017
ROUTER---->DTE----->DCE----->CSU/DSU----->DIGITAL LINE------>WAN SERVICE PROVIDER NETWORK Jul 17, 2017
Router, DTE, DCE, Switch, digital line, WAN Service provider network Jun 23, 2017
Question No : 12 - Topic 1
A receiving host computes the checksum on a frame and determines that the frame is
damaged. The frame is then discarded. At which OSI layer did this happen?
A. session B. transport C. network D. data link E. physical
Answer: D Explanation:
The Data Link layer provides the physical transmission of the data and handles error
notification, network topology, and flow control. The Data Link layer formats the message
into pieces, each called a data frame, and adds a customized header containing the
hardware destination and source address. Protocols Data Unit (PDU) on Datalink layer is
called frame. According to this question the frame is damaged and discarded which will
happen at the Data Link layer.
Data Link Layer Aug 1, 2017
data link layer Jul 31, 2017
Also: The key work in this question is the word FRAME: Frames operate at Layer 2
Application=> Data
Presentation => Data
Session=> Data
Transport =>Segment
Network => Packets
Data link => Frames
Physical =>Bits
Jul 26, 2017
Data Link layer: They are two sublayers LLC=Logical Link Control and MAC=Media Access Control. LLC does error correction. Jul 26, 2017
D. Data Link Layer
Jul 9, 2017
Question No : 13 - Topic 1
Which of the following correctly describe steps in the OSI data encapsulation process?
(Choose two.)
A. The transport layer divides a data stream into segments and may add reliability and flow control information. B. The data link layer adds physical source and destination addresses and an FCS to the segment. C. Packets are created when the network layer encapsulates a frame with source and destination host addresses and protocol-related control information. D. Packets are created when the network layer adds Layer 3 addresses and control information to a segment. E. The presentation layer translates bits into voltages for transmission across the physical link.
Answer: A,D Explanation:
The transport layer segments data into smaller pieces for transport. Each segment is
assigned a sequence number, so that the receiving device can reassemble the data on
arrival.
The transport layer also use flow control to maximize the transfer rate while minimizing the
requirements to retransmit. For example, in TCP, basic flow control is implemented by
acknowledgment by the receiver of the receipt of data; the sender waits for this
acknowledgment before sending the next part.
The Network layer (Layer 3) has two key responsibilities. First, this layer controls the logical
addressing of devices. Second, the network layer determines the best path to a particular
destination network, and routes the data appropriately.
A & D Nov 6, 2017
B. Encapsulation only happens at the data link layer. Oct 5, 2017
Order of encapsulation is important: segment->packet->frame Aug 28, 2017
I thought it was B and D. Encapsulation happens in both layer, no? Aug 9, 2017
A and D Jul 31, 2017
Wrong... The Data Link layer encapsulates a Packet (coming from network layer) within his L2 Header, not a segment (layer 4, Transport Layer) Jul 8, 2017
SEGMENT!
That's the trick Jul 5, 2017
B. The data link layer adds physical source and destination addresses and an FCS to the segment. Jun 23, 2017
Question No : 14 - Topic 1
Refer to exhibit:
Which two destination addresses will be used by Host A to send data to Host C? (Choose
two.)
A. the IP address of Switch 1 B. the MAC address of Switch 1 C. the IP address of Host C D. the MAC address of Host C E. the IP address of the router's E0 interface F. the MAC address of the router's E0 interface
Answer: C,F Explanation:
While transferring data through many different networks, the source and destination IP
addresses are not changed. Only the source and destination MAC addresses are changed.
So in this case Host A will use the IP address of Host C and the MAC address of E0
interface to send data. When the router receives this data, it replaces the source MAC
address with its own E1 interfaces MAC address and replaces the destination MAC
address with Host Cs MAC address before sending to Host C.
C. the IP address of Host C and F. the MAC address of the router's E0 interface. Mar 25, 2018
C and F Jul 31, 2017
Layer 2 Addressing is evaluated in a hop by hop basis, so the data exiting from Host A will have, as layer 2 destination address, the Router E0 Mac Address. Then Router will drop the incoming Ethernet Header, and will put his own header with his Mac Address as source, and Switch 2 Mac Address as Destination... Regarding Layer 3 (IP Addressing) this is related to the entire path, so from the begining of the comunication the IP destination remains the same, Host C IP address... Jul 8, 2017
because you can assume that Hosts and Router are on the same subnet. No VLANs is used, so, only VLAN 1 exists. Jun 22, 2017
A. the IP address of Switch 1
E. the IP address of the router's E0 interface Jun 22, 2017
Why not the mac address of switch 1? Jun 20, 2017
C. the IP address of Host C F. the MAC address of the router's E0 interface May 13, 2017
Question No : 15 - Topic 1
What is the difference between a CSU/DSU and a modem?
A. A CSU/DSU converts analog signals from a router to a leased line; a modem converts analog signals from a router to a leased line. B. A CSU/DSU converts analog signals from a router to a phone line; a modem converts digital signals from a router to a leased line. C. A CSU/DSU converts digital signals from a router to a phone line; a modem converts analog signals from a router to a phone line. D. A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a phone line.
Answer: D Explanation:
CSU/DSU is used to convert digital signals from a router to a network circuit such as a T1,
while a modem is used to convert digital signals over a regular POTS line.
D. A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a pots-line. Mar 25, 2018
D. A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a phone line. Aug 17, 2017
A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a phone line. Jul 31, 2017
D. A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a phone line. Jul 2, 2017
D. A CSU/DSU converts digital signals from a router to a leased line; a modem converts digital signals from a router to a phone line.
question_answerVIEW ANSWER
May 13, 2017
Question No : 16 - Topic 1
Which of the following describes the roles of devices in a WAN? (Choose three.)
A. A CSU/DSU terminates a digital local loop. B. A modem terminates a digital local loop. C. A CSU/DSU terminates an analog local loop. D. A modem terminates an analog local loop. E. A router is commonly considered a DTE device. F. A router is commonly considered a DCE device.
Answer: A,D,E Explanation:
The idea behind a WAN is to be able to connect two DTE networks together through a DCE
network. The networks DCE device (includes CSU/DSU) provides clocking to the DTE-
connected interface (the routers serial interface).
A modem modulates outgoing digital signals from a computer or other digital device to
analog signals for a conventional copper twisted pair telephone line and demodulates the
incoming analog signal and converts it to a digital signal for the digital device. A CSU/DSU
is used between two digital lines -
For more explanation of answer D, in telephony the local loop (also referred to as a
subscriber line) is the physical link or circuit that connects from the demarcation point of the
customer premises to the edge of the carrier or telecommunications service providers
network. Therefore a modem terminates an analog local loop is correct.
A, D, E is the list Aug 1, 2017
A. A CSU/DSU terminates a digital local loop
D. A modem terminates an analog local loop.
E. A router is commonly considered a DTE device. Jun 22, 2017
A. A CSU/DSU terminates a digital local loop. D. A modem terminates an analog local loop. E. A router is commonly considered a DTE device. May 13, 2017
Question No : 17 - Topic 1
Refer to the exhibit. PC_1 is sending packets to the FTP server. Consider the packets as
they leave RouterA interface Fa0/0 towards RouterB. Drag the correct frame and packet
address to their place in the table.
Answer:
Router A Fa 0/0 mac --> Router B Fa0/1 mac --> PC_1 IP address--> FTP IP address Mar 25, 2018
Source Mac : 0000.0c93.9999
Destination Mac : 0000.0c89.3333
Source IP : 172.16.21.7
Destination Mac : 172.16.34.250 Aug 17, 2017
RA Fa 0/0 mac --> R2 Fa0/1 mac --> PC_1 IP --> FTP IP Aug 1, 2017
src mac...9999
dest mac....3333
src ip 172.16.21.7
dest ip 172.16.34.250 Jul 24, 2017
source 0000.0c93.9999 dest 0000.0c89.3333 source ip 172.16.21.7 dest ip 172.16.34.250 Jun 12, 2017
Question No : 18 - Topic 1
Refer to the exhibit.
After HostA pings HostB, which entry will be in the ARP cache of HostA to support this
transmission?
A. Exhibit A B. Exhibit B C. Exhibit C D. Exhibit D E. Exhibit E F. Exhibit F
Answer: A Explanation:
Host A knows host B is in another network so it will send the pings to its default gateway
192.168.6.1. Host A sends a broadcast frame asking the MAC address of 192.168.6.1. This
information (IP and MAC address of the default gateway) is saved in its ARP cache for later
use.
the question is about arp entry. Not about the information in the packet and frame headers. The arp is used by the pc to reach its LAN peers. In this instance your PC wants to reach the default gateway to send the frame in order for the default gateway to forward the frame towards the destination. The correct answer is D Mar 15, 2018
you are not wrong but it is not the right answer. Exhibit D entry will be there in the arp table because it is the default gateway of host A but when host A pings host B a new arp entry will be created as the destination mac address as router 1's physical address as the packet has to go through its gateway but the ip address will be destination IP address i.e. of Host B Nov 19, 2017
So, wouldn't the source and destination MAC address get changed back during the decapsulation process? Nov 1, 2017
the answer is A. ARP cache is the key word. Sep 19, 2017
The answer is D.
The answer key is wrong from the choice, but right on the explanation. Aug 24, 2017
The answer is D. I made the lab no packet tracert and presented the default gateway and mac address of the default gateway! Aug 17, 2017
Yes I agree. Remember, the source and destination MAC changes as each router hop along with the TTL being decremented but the source and destination IP address remain the same from source to destination. Aug 4, 2017
D Jul 31, 2017
The answer is A. The router strips off the source and destination MAC address not the IP address. Jul 30, 2017
I agree just tried the same too Jul 26, 2017
Correct answer is D. Tried similar topology in GNS3, arp shows ip and mac address of default gateway Jun 23, 2017
Answer : D
in the explaination you can see it show answer D is currect Jun 16, 2017
Jun 9, 2017
Destination IP AND Destination Mac address. Jun 2, 2017
Correct answer is D May 25, 2017
The answer is D May 21, 2017
Right answer is D May 13, 2017
SHould be D. Because ARP only show the MAC of devices in local broadcast domain. May 10, 2017
The right answer should be D, I have tried to PING 8.8.8.8, the arp table shows one record only that map default gateway ip with its mac address Apr 30, 2017
Question No : 19 - Topic 1
Refer to the exhibit.
Which three statements correctly describe Network Device A? (Choose three.)
A. With a network wide mask of 255.255.255.128, each interface does not require an IP address. B. With a network wide mask of 255.255.255.128, each interface does require an IP address on a unique IP subnet. C. With a network wide mask of 255.255.255.0, must be a Layer 2 device for the PCs to communicate with each other. D. With a network wide mask of 255.255.255.0, must be a Layer 3 device for the PCs to communicate with each other. E. With a network wide mask of 255.255.254.0, each interface does not require an IP address.
Answer: B,D,E Explanation:
If Subnet Mask is 255.255.255.128 the hosts vary from x.x.x.0 - x.x.x.127 & x.x.x.128-
x.x.x.255, so the IP Addresses of 2 hosts fall in different subnets so each interface needs
an IP an address so that they can communicate each other.
If Subnet Mask is 255.255.255.0 the 2 specified hosts fall in different subnets so they need
a Layer 3 device to communicate.
If Subnet Mask is 255.255.254.0 the 2 specified hosts are in same subnet so are in network
address and can be accommodated in same Layer 2 domain and can communicate with
each other directly using the Layer 2 address.
Got very confused, HT your explanation clarified to me thanks Nov 18, 2017
B, D, E are the correct answers. Aug 1, 2017
BDE is correct answer. Answer B & D is quick to figure out. Explanation of answer D is that Subnet Mask of 255.255.254.0 will have a block size of 2. First subnet will be 10.1.0.0 with host address range of 10.1.0.1 to 10.1.254. Subsequent subnet will be 10.1.2.0, 10.1.4.0 and so on. Therefore both PC interfaces are in the same subnet I,e 1st subnet Jun 23, 2017
Question No : 20 - Topic 1
For what two purposes does the Ethernet protocol use physical addresses? (Choose two.)
A. to uniquely identify devices at Layer 2 B. to allow communication with devices on a different network C. to differentiate a Layer 2 frame from a Layer 3 packet D. to establish a priority system to determine which device gets to transmit first E. to allow communication between different devices on the same network F. to allow detection of a remote device when its physical address is unknown
Answer: A,E Explanation:
Physical addresses or MAC addresses are used to identify devices at layer 2.
MAC addresses are only used to communicate on the same network. To communicate on
different network we have to use Layer 3 addresses (IP addresses) -> B is not correct.
Layer 2 frame and Layer 3 packet can be recognized via headers. Layer 3 packet also
contains physical address ->.
On Ethernet, each frame has the same priority to transmit by default ->.
All devices need a physical address to identify itself. If not, they cannot communicate ->.
A. to uniquely identify devices at Layer 2 E. to allow communication between different devices on the same network. Mar 25, 2018
A. to uniquely identify devices at Layer 2
E. to allow communication between different devices on the same network Aug 7, 2017
A modem modulates outgoing digital signals from a computer or other digital device to
analog signals for a conventional copper twisted pair telephone line and demodulates the
incoming analog signal and converts it to a digital signal for the digital device. A CSU/DSU
is used between two digital lines -
For more explanation of answer D, in telephony the local loop (also referred to as a
subscriber line) is the physical link or circuit that connects from the demarcation point of the
customer premises to the edge of the carrier or telecommunications service providers
network. Therefore a modem terminates an analog local loop is correct.
