Docsity
Docsity

Prepare for your exams
Prepare for your exams

Study with the several resources on Docsity


Earn points to download
Earn points to download

Earn points by helping other students or get them with a premium plan


Guidelines and tips
Guidelines and tips

Cell Switching - Internetworking and Security - Past Exam, Exams of Computer Networks

Main points of this past exam are: Cell Switching, Traffic Contract, Traffic Control Techniques, Core Networks, Carrying Voice, Video, Data Traffic, Services Simultaneously, Addressing, Network Consists

Typology: Exams

2012/2013

Uploaded on 03/24/2013

anagha
anagha 🇮🇳

4.4

(43)

131 documents

1 / 3

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
Cork Institute of Technology
Bachelor of Science (Honours) in Software Development and
Computer Networking - Stage 3
(KDNET_8_Y3)
March 2008
Internetworking and Security
(Time: 3 Hours)
Answer any FOUR questions
All questions carry equal marks
Examiners: Ms.Olivia Brickley
Mr. J. Buckley
Mr. A. Kinsella
Q.1 a. Many public carriers are deploying ATM in their core networks as an
infrastructure for carrying voice, video and data traffic. Describe how ATM
facilitates these services simultaneously, addressing the following:
Cell switching
Traffic contract
Traffic control techniques (10 marks)
b. An ATM network consists of a set of ATM switches interconnected by point-to-
point ATM links or interfaces. Illustrate a typical ATM network, identifying the
four types of ATM interface. (5 marks)
Illustrate and explain how the interface type influences the ATM cell header? (5 marks)
c. Compare and contrast PVCs and SVCs. A soft PVC provides the flexibility of
SVCs and the stability of PVCs. Explain (5 marks)
pf3

Partial preview of the text

Download Cell Switching - Internetworking and Security - Past Exam and more Exams Computer Networks in PDF only on Docsity!

Cork Institute of Technology

Bachelor of Science (Honours) in Software Development and

Computer Networking - Stage 3

(KDNET_8_Y3)

March 2008

Internetworking and Security

(Time: 3 Hours)

Answer any FOUR questions All questions carry equal marks

Examiners: Ms.Olivia Brickley Mr. J. Buckley Mr. A. Kinsella

Q.1 a. Many public carriers are deploying ATM in their core networks as an infrastructure for carrying voice, video and data traffic. Describe how ATM facilitates these services simultaneously, addressing the following:

  • Cell switching
  • Traffic contract
  • Traffic control techniques (10 marks)

b. An ATM network consists of a set of ATM switches interconnected by point-to- point ATM links or interfaces. Illustrate a typical ATM network, identifying the four types of ATM interface. (5 marks) Illustrate and explain how the interface type influences the ATM cell header? (5 marks)

c. Compare and contrast PVCs and SVCs. A soft PVC provides the flexibility of SVCs and the stability of PVCs. Explain (5 marks)

Q2. a. Explain, with the aid of a diagram, the Q931 call setup procedure for ISDN BRI. (5 marks)

b. What is enbloc sending? How does this differ from overlap sending during the Q931 call setup procedure? (5 marks)

c. A Frame Relay PVC has an agreed data rate, the committed information rate. Identify the relationship between CIR and committed burst size, excess burst size, and explain how frames are transmitted on a PVC taking into account these parameters. (8 marks)

d. What is the purpose of the FECN and BECN bits in a LAPF frame? How is the DE bit used? (6 marks) In Frame relay, multiple connections are configured over one physical connection. How is this possible? (1 mark)

Q3. a. What is a security policy and what are its benefits? (2 marks)

b. The three security policy components are identity, integrity and active audit. Describe the aspects of network security addressed in each, identifying possible solutions. (9 marks) c. Describe the AH and ESP protocols defined in IPSec, outlining the services they provide. Using diagrams, explain the difference between tunnel and transport mode. (8 marks)

d. What is a Denial of Service (DoS) attack? Identify four types of DoS attack, outlining how these could be thwarted. (6 marks)

Q4. a. Explain the function of a DIFS, SIFS and PIFS in 802.11, giving possible values for these parameters. (6 marks)

b. DCF uses CSMA/CA to allow multiple independent stations to share the wireless channel. Explain its operation. (8 marks)

c. Given the network address 192.159.145.0/26 and assuming the use of subnet#0, use VLSM to design an efficient subnetting scheme to allow for: i. 2 subnets with up to 30 hosts ii. One subnet with up to 10 hosts iii. One subnet with up to 6 hosts iv. 2 subnets with 2 hosts (6 marks)

d. What is IP multicast? List its advantages and drawbacks. (5 marks)