connecting networks

1. NATIONAL INSTITITUTE OF BUSINESS MANAGEMENT
Diploma in Computer Networks 17.1F
Connecting Networks-DCN-3-4-11
Date:04 June 2018 Time Allowed: 3hrs
Answer all the questions. All questions carry equal marks. Calculators are not allowed.
1.A small company with 10 employees uses a single LAN to share information between
computers. Which type of connection to the Internet would be appropriate for this company?
a) Private dedicated lines through their local service provider
b) A dialup connection that is supplied by their local telephone service provider
c)Virtual Private Networks that would enable the company to connect easily and
securely with employees
d) A broadband service, such as DSL, through their local service provider
2.Which broadband technology would be best for a small office that requires fast upstream
connections?
a) fiber-to-the-home
b) WiMax
3. What is a disadvantage of leased lines?
a) low quality
b) inconsistent availability
c) DSL
d) Cable
c) complexity
d) high cost
4. Which of the following PPP protocol allows a device to specify an IP address for routing
over the PPP link?
a) PAP
b) CHAP
c) LCP
d) IPCP
5. PPP authentication is performed at which of the following OSI layers?
a) Layer 1
b) Layer 2
c) Layer 3
d) Layer 4
6.Which of the following additional functionality is available on an interface when the
encapsulation is changed from HDLC to PPP?
a) flow control
b) error control
c) authentication
d) synchronous communication
7. What are the two types of VPN connections? (Choose two of the answers.)
a) PPPoE
b) site-to-site
c) leased line
d) Frame Relay
e) remote access
8. Which troubleshooting method begins by examining cable connections and wiring issues?
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2. a) top-down
b) divide-and-conquer
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c) substitution
d) bottom-up
9. What is an advantage offered by GRE tunnels?
a) built in security mechanisms
b) encryption of encapsulated traffic
c) support for IP multicast tunneling
d) support for connecting individual hosts across the Internet
10. What TCP port is used by BGP to exchange messages between routers?
a) 22
b) 58
c) 179
d) 443
11. Which of the following statements describe a characteristic of standard IPv4 ACLs?
a) They are configured in the interface configuration mode.
b) They filter traffic based on source IP addresses only.
c) They can be created with a number but not with a name.
d) They can be configured to filter traffic based on both source IP addresses and
source ports.
12.What range of IP addresses is represented by the network and wildcard mask
192.168.70.0 0.0.0.127?
a) 192.168.70.0 to 192.168.70.127
b) 192.168.70.0 to 192.168.70.255
c) 192.168.70.0 to 192.168.70.63
d) 192.168.70.0 to 192.168.71.255
13. What is the only type of ACL available for IPv6?
a) named standard
b) named extended
c) numbered standard
d) numbered extended
14.A networked PC is having trouble accessing the Internet, but can print to a local printer
and ping other computers in the area. Other computers on the same network do not have
any issues. What is the problem?
a) The PC has a missing or incorrect default gateway.
b)The link between the switch to which the PC connects and the default gateway
router is down.
c) The switch port to which the PC connects has an incorrect VLAN configured.
d) The default gateway router does not have a default route.
15. Which of the following modes is used to configure SNMP?
a) privileged mode
b) global configuration mode
c) interface configuration mode
d) router configuration mode
16. What is an SNMP management agent?

3. a) a computer loaded with management software and used by an administrator to
monitor a network
b) a database that a device keeps about network performance
c) software that is installed on devices managed by SNMP
d) a communication protocol that is used by SNMP
17.What is the best mitigation plan for thwarting a DoS attack that is creating a switch buffer
overflow?
a) Disable DTP.
b) Disable STP.
c) Enable port security.
d) Place unused ports in an unused VLAN.
18.Which of the following protocol or service allows network administrators to receive
system messages that are provided by network devices?
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a) SNMP
b) syslog
c) NetFlow
d) NTP
19. Which type of traffic does Cisco recommend be placed in the strict priority queue (PQ)
when low latency queuing (LLQ) is being used?
a) video
b) data
c) voice
d) management
20. Which protocol or service allows network administrators to receive system messages
that are provided by network devices?
a) SNMP
b) syslog
c) NetFlow
d) NTP
Part B
Answer All questions. The marks given in brackets are indicative of the weight given
to each part of the question
B1. A WAN operates beyond the geographic scope of a LAN.
a) What is the difference between LAN and WAN? (4 marks)
a) List 3 Common WAN topologies with the diagrams (6 marks)
b) Identify (Using a Diagram) and fill the table using the WAN Terms given below
(5Marks)
briefly describe WAN Terms given below (5marks)
CPE | DCE | DTE | Demarcation Point | Local Loop
WAN Term
A
B
C
D
E

4. B2. The following question is on Network Security, Monitoring and troubleshooting.
a) The SNMP system consists of three elements. List the 3 elements. (3 marks)
b) What are the port numbers that are used by SNMP? (2 marks)
c) What is the advantage over Switched Port Analyzer (SPAN) feature? (3 marks)
d) What is ACL Packet Filtering? (2 marks)
e) Briefly describe the below ACL Statements? Specify the ACL type. (4 marks)
f)Briefly explain the layered troubleshooting approach (including three methods)? (6
marks)
B3 a) Briefly describe terms given below (8 marks)
Bandwidth, Congestion, Delay, and Jitter
b) Match each item given below to its description (6 marks)
Code delay | Propagation Delay | Packet Loss | jitter | Queue | Bandwidth |
serialization Delay | Congestion
1.This happens when congestion occurs
2.The fixed amount of time it takes to transmit a frame from the NIC to the
Wire.
3. Holds packets memory until resources become available to transmit them.
4. The Number of bits that Can transmitted in a Single second.
5.The fixed amount of time it takes to compress data at the source before
transmitting to the first networking device
6. When the demand for bandwidth exceeds the amount available
c) What is Traffic policing? (2 marks)
d) Write three advantages of virtualization? (2 marks)
e)Cloud services are available in a variety of options, tailored to meet customer
requirements. The three main cloud computing services defined by the National
Institute of Standards and Technology (NIST) in their Special Publication 800-145.
List down three cloud computing services? (2 marks)
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