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NoteNWC

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HTML is used to create and format Web pages while HTTP is used to
transmit the web pages over the network.
Which of the following is used to check the route that an IP packet traversesfrom one host to
another host?
A. FTP
B. Tracert
C. ICMP
D. Telne
Which flag bit in TCP header must be set when a TCP entity wants to terminate a connection?
A. FIN
B. SYN
C. RST
D. ACK
Transmission Control Protocol (TCP), has same Checksum controlling like
A. TCP/IP
B. ICMP
C. UDP
D. IP
Which of the following networks can be connection-oriented?
A, Telegraph networks
B, Computer networks
C, Telephone networks
D, All of the above
A protocol is a set of precise and unambiguous rules that governs
A, How two or more communicating entities in a layer are to interact
B, Messages that can be sent and received
C, Actions that are to be taken when a certain event occurs
D, All of the above
D
DNS is a domain-name-service that responds to queries of domain name to IP address or IP
address to domain name. DNS uses services provided by
A, TCP
B, UDP
C, HTTP
D, None of the above
B
A network used to join the individual networks at different sites into one extended network is called
A, PAN
B, LAN
C, SAN
D, VPN
D
Upon receipt of a bad segment, UDP?
A, It does flow control
B, It does not do flow and error control
C, It does error control
D, Retransmission
B
Which of following protocol is HTTP built upon?
A, IP
B, TCP
C, UDP
D, SMTP
1. Which three layers of the OSI model make up the application layer of the
TCP/IP model? (Choose three.)
A. data link
B. application
C. presentation
D. session
E. transport
F. Network
2. Which two layers of the OSI model specify protocols that are associatedwith
Ethernet standards? (Choose two.)
A. session layer
B. physical layer
C. transport layer
D. data link layer
3. When you first log into the router, in which command mode do you enteras
indicated by the > symbol?
A. user EXEC mode
B. privileged EXEC mode
C. line configuration mode
D. global configuration mode: A. user EXEC mode
4. Which Cisco IOS mode displays a prompt of Router#?
A. privileged EXEC mode
B. global configuration mode
C. user EXEC mode
setup mode
5. Which IP address type is intended for a specific host?
A. broadcast
B. multicast
C. simulcast
D. unicast:
6. Which type of packet goes to all hosts on a LAN?
A. unicast
B. multicast
C. broadcast
7. What type of message is sent to a specific group of hosts?
A. unicast
B. dynamic
C. multicast
D. broadcast
8. Which IP configuration parameter provides the IP address of a network
device that a computer would use to access the Internet?
A. default gateway
B. host IP address
C. subnet mask
D. DNS server
Which network device is primarily used to translate a domain name to the associated IP
address?
A. router
B. DNS server
C. DHCP server
D. default gateway
Which device will not forward an ARP request to other hosts in the network?
A. Switch
B. Hub
C. PDU
D. Router
Usually in the home network, only 1 device is used to connect the laptop, desktop to the
Internet regardless the UTP cable is plug-in or not. This device must perform function
belong to which of the following?
A. Modem
B. Router
C. Switch
D. Wireless access point
E. All of the others
What role does a router play on a network?
A. forwarding Layer 2 broadcasts
B. forwarding frames based on a MAC address
C. selecting the path to destination networks
D. connecting smaller networks into a single broadcast domain
9. What is used by a host to determine if another host is on the same
network?
A. ARP
B. default gateway
C. MAC address table
D. subnet mask
10. Which layer has the same functionality in both the OSI and TCP/IP models?
A. Application
B. Presentation
C. Session
D. Transport: D. Transport
11. Which layer provides connections to hosts in a local Ethernet network?
A. core layer
B. network layer
C. internet layer
D. access layer: D. access layer
12. Which layered model was first used for internetwork communications?
A. encapsulation
B. IETF
C. OSI Model
D. Reference Model
E. TCP/IP Model
One can use repeaters, bridges and routers to interconnect two LANs. Which of the
following approaches will make local traffic appear in both LANs?
A. Repeater
B. Routers
C. Bridges
D. All of the others
Which application layer protocol is used to provide file-sharing and print services to Microsoft
applications?
A. DHCP
B. SMB
C. SMTP
D. HTTP
13. Which protocol allows a user to type www.cisco.com instead of an IP
address to access the web server?
A. SNMP
B. DNS
C. HTTP
D. FTP
E. HTML
This protocol is used by a client to send email to a mail server.
A. HTTP
B. POP
C. IMAP
D. SMTP
Which two protocols are used in the process of sending and receivingemails?
(Choose two.)
A. FTP
B. HTTP
C. SMTP
D. SSH
E. POP
What feature allows a device to obtain an address automatically?
A. TCP/IP
B. ping
C. ip autoconfig
D. DHCP
Which command was used to view the IP address configuration of the PC?
A. DHCP
B. ip address
C. ipconfig/ all
D. network settings
14. What command is used to save the switch configuration?
A. ipconfig/ all
B. save config
C. copy config
D. copy running-config startup-config
E. save config all
15. What command was used to verify the router configurations?
A. verify config
B. letmein
C. show running-config
D. view configuration
copy running-config startup-config
16. What is the purpose of an IP address?
A. It identifies the physical location of a data center.
B. It identifies a location in memory from which a program runs.
C. It identifies a return address for replying to email messages.
D. It identifies the source and destination of data packets on a network.
17. What is the purpose of assigning an IP address to the VLAN1 interface on a Cisco Layer 2
switch?
A. to create a new IP local network on the switch
B. to enable the switch to route packets between networks
C. to permit IP packets to be forwarded by the switch
D. to enable remote access to the switch to manage it
18. What is the purpose of configuring a default gateway address on a host?
A. to identify the device that allows local network computers to communicatewith devices on
other networks
B. to provide a permanent address to a computer
C. to identify the logical address of a networked computer and uniquelyidentify it to the
rest of the network
D. to identify the network to which a computer is connected
19. What is the purpose of DHCP?
A. gives clients the option to statically or dynamically assign itself an address
B. provides a mechanism for the automatic assignment of addressing information for a client
C. provides DNS addressing information to clients
D. allows for the reuse of addresses on a network
What is the purpose of NAT?
A. provides a way to translate URLs to IP addresses
B. finds the MAC address when the IP address is known
C. maps and translates between public and private IP addresses
D. creates a table of switch ports to MAC addresses
Which type of attack attempts to overwhelm network links and devices with useless
data?
A. virus
B. spyware
C. brute force
D. denial of service
Which type of attack exploits human behavior to gain confidential information?
A. virus
B. social engineering
C. denial of service
D. spyware
What type of program installs and gathers personal information, including password
and account information, from a computer without permission or knowledge of the
user?
A. adware
B. pop-ups
C. spyware
D. pop-unders
Which function does NAT perform in a wireless router?
A. NAT takes a source IP address and translates it to a default gateway
address.
B. NAT takes a local IP address and translates it to an internal source IP
address.
C. NAT takes a destination IP address and translates it to a global IP
address.
D. NAT takes an internal source IP address and translates it to a global IP
address.
20. What is the purpose of the console port?
A. provide in-band management of the switch
B. send data between two host computers
C. to connect the switch to the router
D. provide out-of-band management for a router or switch:
21. What is the purpose of the core layer in the Cisco hierarchical
networkdesign model?
A. network access to end devices
B. high-speed backbone switching
C. aggregation point for smaller networks
D. flow control between networks
Which of following features are typically true for local area networks?
A. Low round-trip delay
B. Low error rate
C. High speed
D. All of the others
In Carrier Sense Multiple Access with collision detection (CSMA-CD), how
long will it take a collision to be detected and resolved?
A. Round-trip propagation delay
B. One propagation delay
C. One frame transmission time
D. None of the others
For a 10Mbps Ethernet link, if the length of the packet is 32bits, the
transmission delay is (in microseconds)?
A. 320
B. 0.32
C. 3.2
D. 32
In which order do the DHCP messages occur when a client and server are
negotiating address configuration? Discover – offer – request - pack
Using a systematic troubleshooting approach, a help desk technician suspects
a problem at Layer 3 of the OSI model. In gathering information, which two
questions are associated with Layer 3? (Choose two.)
A. From the PC, is the default gateway reachable using the ping command?
B. Does a browser connection to www.cisco.com work?
C. Is the network cable plugged in?
D. Is the PC configured for DHCP?
E. Is there a link light on the network card?
In a virtual-circuit packet network, routing is determined during connection
set-up
True
False
Following the above question, in the third algorithm iteration, which
nodes will update their entries and inform their neighbors?
3
4
6
All of the above
Consider the network as shown in the figure. We use the Bellman-Ford
algorithm to find the set of shortest paths from all nodes to the destination
node 2. Each node maintains an entry (n, cost) about the next node along the
current shortest path and the current minimum cost from the node to the
destination. Initially, each node has entry (-1, infinity).
In the first algorithm iteration, which nodes will update their entries and
inform their neighbors?
1
4
5
All of the above
What are possible metrics for routing?
Hop count
Delay
Bandwidth
All of the above
Six stations (S1-S6) are connected to an extended LAN through transparent
bridges (B1 and B2), as shown in the following figure. Initially, the
forwarding tables are empty. Both bridges use backward learning to build
their tables. Suppose station S2 transmits a frame to S1. Which of following
statements is correct?
The frame will reach bridge B2 only
None of the above
The frame will reach both bridges B1 and B2
The frame will reach bridge B1 only
Consider a three hop network from the source to the destination. Let m be the
message transmission time at each hop. Let n be the propagation delay of
each hop. Assume there is no queueing delay and processing time at each
hop. Based on store-and-forward, what is the total time for three packets to be
transmitted to the destination by packet pipelining?
3m + 3n
5m + 3n
9m + 9n
None of the above
Which of the following features are true for asynchronous transfer mode
(ATM)?
It supports quality of service
All of the above
It is connection-oriented
It only supports fixed-length packets
Consider the network as shown in the figure. We use the Dijkstra's algorithm
to find the set of shortest paths from all nodes to the destination node 4. In
Dijkstra's algorithm, each iteration the next closet node is added to the set
with the root node.
At the first iteration, which node will be added to the set N?
1 / 1 point
5
1
3
2
Question 3
Following the question above, at the second iteration, which node will be
added to the set N?
1 / 1 point
6
5
3
1
Question 4
Following the question above, at the third iteration, which node will be
added to the set N?
1 / 1 point
5
1
3
6
Following the question above, at the fourth iteration, which node will be
added to the set N?
3
1
6
5
What are the limitations of RIP protocol
Limited metric use
Slow convergence
Fixed number of hops
Update message overhead
In Open Shortest Path First (OSPF), which of the following statements are
correct
1 / 1 point
Allows routers to build shortest path tree with router as root
OSPF typically converges slower than RIp when there is a failure in the
network
Each router builds an identical link-state database
Enables each router to learn complete network topology
Which of the following is a type of router defined in OSPF
1 / 1 point
Internal router
Area border router
Backbone router
All of the above
In a distance vector routing, if a link fails
All routers immediately update their link database and recalculate their
shortest path
Neighboring routers exchange routing tables that may use failed links
Routers set link distance to infinity and floods the network with an update
packet
All of the above
Which of the following statements is wrong about fair queuing?
1 / 1 point
Fair queueing is a packet-level traffic management
Fair queueing attempts to provide equal-size buffers to flows
Fair queueing attempts to provide equitable access to transmission bandwidth
All of the above
To guarantee network performance during the lifetime of admitted flows,
open-loop control relies on the following mechanism except:
1 / 1 point
Admission control
Traffic policing
Traffic shaping
Head-of-Line queueing
Which of following statements about leaky bucket is wrong?
Leaky bucket is a flow-level traffic management mechanism
In the leaky bucket, the packet output rate can be variable
In the leaky bucket, the packet output rate is always constant
In leaky bucket, when the bucket is full, the new arriving packets may be
discarded
Upon which of the following condition is token bucket and leaky bucket the
same?
A. Leaky bucket size is zero
B. Token bucket size is infinite
C. Leaky bucket size is infinite
D. Token bucket size is zero
In Head of Line (HOL) priority queueing, which of the following statement is
true for this approach
A. High priority queue has higher waiting time
B. Buffers can be dimensioned for different loss probabilities
C. High priority queue has lower waiting time
D. High priority queue services until empty
In buffer management, which of the following statement is correct for
Random Early Detection (RED) technique
A. Improves performance of cooperating TCP sources
B. Reduce loss probability of misbehaving sources
C. Packets produced by TCP will reduce input rate in response to network
congestion
D. Early drop causes some sources to reduce rate before others, causing
gradual reduction in in aggregate input rate
Which of the following packet header length cannot be used in an IPv4 packet
header?
A. 20 Bytes
B. 30 Bytes
C. 60 Bytes
D. 64 Bytes
What is the dotted notation of an IP address of 10000000 10000111 01000100
00000101 ?
A. 128.135.65.5
B. 128.135.65.5
C. 128.135.68.5
D. 128.133.68.5
Given a network address 128.100.0.0, what is its network class type?
A. Class A
B. Class B
C. Class C
D. None of the above
Based on 1.1.1.0/24, the IP address would be:
A. Class A
B. Class B
C. Class C
D. Class D
Which class of IP addresses does CIDR performs aggregation on?
A. Class C
B. Class D
C. Class B
D. Class A
When calculating usable hosts per subnet, the following formula is used
2^bits - 2. For what reason is two subtracted? (choose two)
A. Broadcast
B. Network
C. Unicast
D. Multicast
AB
How many hosts can be addressed on 10.0.0.0/16?
A. 16
B. 254
C. 65536
D. 65534
D
Which of the following is a valid IP host address given the network ID of
191.254.0.0 while using 11 bits for subnetting?
A. 191.254.1.29
B. 191.254.0.32
C. 191.54.1.64
D. 191.254.0.96
A
DISCO Corporation has been assigned the Class B network address 165.87.0.0.
DISCO needs to divide the network into eight subnets. What subnet mask
should be applied to the network to provide the most hosts per subnet?
A. 255.255.240.0
B. 255.255.248.0
C. 255.255.192.0
D. 255.255.224.0
In NAT operations, which of the following statements are correct
A. NAT maps each private IP address and port number into shared global IP
address and available port number
B. Hosts inside private networks generate packets with private IP address and
TCP/UDP port numbers
C. Translation table allows packets to be routed unambiguously
D. Translation table allows packets to be routed ambiguously
ABC
Pv6 allows fragmentation at
A. Source only
B. Intermediate routers only
C. Both source and intermediate routers
D. None of the above
A
IPv6 has a much larger space of
A. 2^8
B. 2^16
C. 2^32
D. 2^128
Which of these statements are true of IPv6 representation
A. The first 64 bits represent the dynamically created interface ID.
B. Leading zeros in an IPv6 16 bit hexadecimal field are mandatory
C. A single interface may be assigned multiple IPv6 addresses of any type
D. Every IPv6 interface contains at least one loopback address
In TCP/IP protocol, what is the decimal range of the first octet of class
Aaddress?
A. 0 –126
B. 0– 127
C. 1–126
D. 1–127
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