1. NATIONAL INSTITUTE OF BUSINESS MANAGEMENT
Diploma in Computer Networks 18.1F
Connecting Networks – DCN-3-4-11
The exam has Two (Part A and Part B) Parts. You must answer both parts.
Calculators are not allowed.
Date:07-06-2019 | Time:0900-1200
Part A
Answer all questions. All questions carry equal marks.
Duration:3 Hours
1.Which two WAN infrastructure services are examples of private connections? (Choose
two.)
a) T1/E1
b) wireless
c) DSL
d) cable
e) Frame Relay
2.Which three traffic-related factors would influence selecting a particular WAN link type?
(Choose three.)
a) type of traffic
b) amount of traffic
c) cost of the link
d) security needs
e) distance between sites
f) reliability
3. What is a disadvantage of leased lines?
a) low quality
b) inconsistent availability
c) complexity
d) high cost
4.Which 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 OSI layer?
a) Layer 1
b) Layer 2
c) Layer 3
d) Layer 4
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2. 6. Which additional functionality is available on an interface when the encapsulation is
changed from HDLC to PPP?
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a) Flow control
c) Authentication
b) error control
d) synchronous communication
7. What are the two types of VPN connections? (Choose two.)
a) PPPoE
b) site-to-site
c) leased line
d) Frame Relay
e) remote access
8.Which two components are needed to provide a DSL connection to a SOHO? (Choose
two.)
a) transceiver
b) DSLAM
c) CMTS
d) CM
e) PPPoE enabled switch
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 troubleshooting tool can be used to pinpoint the distance to a break in a network
cable?
a) digital multimeter
b) network analyzer
c) network analysis module
d) cable tester
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
3. 13. What is the only type of ACL available for IPv6?
a) named standard
b) named extended
c) numbered standard
d) numbered extended
14.An administrator has configured an access list on R1 to allow SSH administrative access
from host 172.16.1.100. Which command correctly applies the ACL?
a) R1(config-if)# ip access-group 1 in
b) R1(config-if)# ip access-group 1 out
c) R1(config-line)# access-class 1 in
d) R1(config-line)# access-class 1 out
15. Which mode 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?
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 mitigation plan is best 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.An attack has been launched within a company and a host name has been identified as
the source. What command can a network technician use to determine the IP address
assigned to the host name?
a) ipconfig /all
b) net computer
c) nslookup
d) tracert
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
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4. 20.Which Cloud computing service would be best for an organization that needs to
collaboratively create applications and deliver them over the web?
a) PaaS
b) IaaS
c) SaaS
d) ITaaS
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)
b) List 3 Common WAN topologies with the diagrams? (6 marks)
c) Identify and briefly describe below WAN Terms using diagram? (10 marks)
CPE
DCE
DTE
Demarcation Point
Local Loop
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B2. This question is about the Network Security and Monitoring
a) The SNMP system consists of three elements. List that 3 elements? (3 marks)
b) What are the ports numbers that used by SNMP? (2 marks)
c) Write down two different between SNMPv2c and SNMPv3? (4 marks)
d) What is the mitigation mechanism for DHCP spoofing attack?
Briefly describe that mechanism. (4 marks)
e) What is the advantage over Switched Port Analyzer (SPAN) feature? (3 marks)
f) Briefly describe below DHCP attacks types? (4 marks)
a) DHCP spoofing attack
b) DHCP starvation attack
B3. This question is about the WAN concepts.
a) Briefly explain about Point to Point connections? (2 marks)
b) What are the advantages of PPP encapsulation? List Three (3 marks)
c) Briefly Describe below terms? (8 marks)
IGP
EGP
iBGP
eBGP
d) What is VPN? (3 marks)
e) What are the main two types of VPN types? briefly Describe. (4 marks)