Networks & Applications3

For 112 semester
Networks & Applications
INFT12/72-230
Assignment 3
Due: 4 pm Monday of Week 13 (8th August 2011)
Credit: 15 marks
In this assignment you are requested to answer the four questions:
Question 1: (4 marks)
A router has the following (CIDR) entries in its routing table:
Address/mask Next hop
135.46.56.0/22 Interface 0
135.46.60.0/22 Interface 1
192.53.40.0/23 router 1
default router 2
For each of the following IP addresses, what does the router do if a packet with that address arrives?
(a) 135.46.63.10
(b) 135.46.57.14
(c) 135.46.52.2
(d) 192.53.40.7
(e) 192.53.56.7
Question 2: (3 marks)
Write HTML codes which output the following table or layout. You need to display text and colour fields, but borders need not be shown.
Question 3: (3 marks)
Review all the Java classes given in the folder called TCPThreaded from lab7.zip for workshop 7. It’s a complete example for TCP simple application, called “Score Service”, which can be used for developing networked computer games. It consists of client and server programs. The server maintains a high scores list, and the client reads and adds scores to the list. In this implementation, the server is threated, enabling it to process multiple clients at the same time. Have a practice with this TCP application. You may create two “commands” windows, one for server and another for client.
List all the Java classes, provided by Java 1.6 API from the following link,
, which are related the concept of socket for communication between client and server. Briefly describe the functions of each such class.
Question 4: (4 marks)
A client computer is linked via Ethernet LAN to a default router, through which the client may communicate with its server on the Internet. The ARP cache of this client is
shown below:
client# arp -a
Net to Media Table
Device IP Address Mask Flags Phys Addr
—— ——————– ————— —– —————
hme0 default router 255.255.255.255 00:e0:f7:26:3f:e9
hme0 client 255.255.255.255 SP 08:00:20:86:35:4b
hme0 224.0.0.0 240.0.0.0 SM 01:00:5e:00:00:00
This shows the physical (MAC) address of the router and the physical (MAC) address of the client itself. A single Ethernet packet was sent from the client to the server using the UDP transport service. The hexadecimal dump of the packet in the client is shown as below:
0: 00e0 f726 3fe9 0800 2086 354b 0800 4500 ..÷&?… .5K..E.
16: 0026 ab49 4000 ff11 f700 8b85 d96e 8b85 .&.I@…÷….n..
32: e902 99d0 043f 0012 7228 6865 6c6c 6f68 …..?..r(helloh
48: 656c 6c6f ello
Decode this Ethernet packet and fill out the following list:
ETHER: —– Ether Header —–
ETHER:
ETHER: Packet 16 arrived at 17:40:4.69
ETHER: Packet size = 52 bytes
ETHER: Destination =
ETHER: Source =
ETHER: Ethertype =
ETHER:
IP: —– IP Header —–
IP:
IP: Version =
IP: Header length =
IP: Type of service =
IP: Total length =
IP: Identification =
IP: Flags = 0x4
IP: .1.. …. = do not fragment
IP: ..0. …. = last fragment
IP: Fragment offset =
IP: Time to live =
IP: Protocol =
IP: Header checksum =
IP: Source address =
IP: Destination address =
IP: No options
IP:
UDP: —– UDP Header —–
UDP:
UDP: Source port =
UDP: Destination port =
UDP: Length =
UDP: Checksum =
UDP:
UDP: Data
NOTES:
Submission procedure: your work for this assignment must be submitted into the Faculty Assignment Box located in Building 2 (School of Business), at Level 2 Reception. (Currently, the reception is temporarily moved to Doctor’s Office, beneath Gymnasium).
The due date for the assignment is a hard date. You will need to supply a good reason if an extension is required. Unless you have given me your written request for extension, and I have approved an extension (along with my signature), late submissions will not be accepted. This assignment is worth 15% of your final mark in this course.
The course rules on own work and plagiarism apply to this assignment. See the subject outline page for details from the iLearn web site. Your submission will be cross-compared to other student submissions to ensure that answers have not been shared.
from Dr. Zheng da Wu

ICT’s in a global context Essay

I CT in a Global Context

CW1
Weighting: 40%

There is a tension within the ICT and development discourse between those who see ICTs as the development saviour and those who are more skeptical and who do attempt to draw attention to the social, cultural, economic and political environment within which a country development efforts are embedded.

Use the knowledge and learning you have acquired on module to discuss this statement in the form of a 1500 essay. You will be assessed on the following:

 

Marking criteria:

Ability to write an academic essay
Ability to critically analyse the statement
Ability to apply theory to support your arguments
Evidence of research and application of knowledge obtained in your discussion
Clear essay structure including an introduction
References and an appropriately formatted bibliography
Careful proofreading for grammar, spelling, sentence construction and clarity
Wordprocessing (Times New Roman Font size 12, and 1.5 line spacing)

Assignment 2

 

Networks & Applications

 

Task 1: Wireless Wide Area Networks (6 marks)

 

Using the Internet online services, learn the basic knowledge about wireless wide area network technologies, particularly for mobile phone and data services, and answer the following questions:

  1. What is the concept of a cellular network or system? Give a network example to illustrate this concept.
  2. What are the key differences between the Global System for Mobile Communications (GSM) network and the 3rd generation mobile telecommunications (3G) network standardized by 3GPP in their architecture?
  3. What are the radio transmission technologies used for the GSM and the 3G network in the physical layer respectively? What data rate can each network support?
  4. What is the facility used to achieve the mobility management (or roaming) in the GSM network? Does the 3G network use the same mobility management system equipped in the GSM?

Task 2: IP addresses allocation (4 marks)

 

A large number of consecutive IP addresses are available starting from 198.16.0.0. Suppose that four organizations, A, B, C and D, request 4000, 2000, and 4000, and 8000 addresses, respectively, and in that order. For each of these, give the first IP address assigned, the last IP address assigned, and mark in the  w.x.y.z/s notation (for example, 135. 46.56.0/22).

 

Task3: Subnet a network (5 marks)

 

Assume that you have purchased the IP network 213.45.32.0/20 from APNIC. Subnet this network so that all of the broadcast domains shown in the below diagram are allocated individual subnets. Create a table with the following headings which lists the subnets that you have created:

  • Location: e.g. LAN 1
  • Subnet Identity
  • Netmask
  • Range of Usable IP Addresses: give the range of usable IP addresses on this subnet, e.g. 1.2.0.1 to 1.2.0.254

In a separate table, allocate suitable IP addresses for every router and stations A, P and X. Remember, every port on a router has its own IP address. Allocate your own port numbers for each router. Do not put an IP address on Router 2’s port connected to the Internet, as it will get an IP address on this port from your ISP. Write the table out with the following headings:

  • Device: e.g. A, or Router 1 port 0.
  • IP Address

(Notes: the number of stations for each LAN is important for your answer now.)

 

 

Task 4: Routing with Packet Tracer (5 marks)

 

Using the IP addresses from your subnetting, build the above diagram as shown in Packet Tracer. You will create and save a Packet Tracer scenario file in this task. Make sure that all devices and physical connections are represented in your scenario. Give the Internet, indicated in the diagram, the IP address of 131.200.0.0/16, and give Router 2’s Internet port the IP address 131.200.1.1/16.

 

Ensure that stations A, P and X can send packets to each other and to the Internet.

 

NOTES:

Your work for Task 4, saved as a Packet Tracer’s file.

 

System Security

Scenario:

People’s Bank and Trust is a full-service, privately owned community bank. The bank is divided into the following departments: Customer Service, Loans, Business Services, and Investment Services. The bank is presently upgrading its servers from Windows Server 2003 to Windows Server 2008. Also, it is gradually upgrading client computers from a mix of Windows 2000 and XP to Windows Vista. The cash drawers at the tellers’ booths are connected to Windows XP computers, which are networked into the servers. The bank uses Active Directory with one small domain and with OUs for each department. All of the servers at the bank are configured as DCs.

In addition to walk-in and drive-up services, People’s Bank offers ATM services and Internet banking. The Internet banking is performed through a Windows Server 2003 Web server located at the bank. The bank also offers automated telephone banking services that are tied into its Windows servers.

The bank auditors have recently raised concerns in several areas of computer and network security that the bank wants to address at the same time as it upgrades the client and server computers. The IT director at the bank has retained you via Aspen Consulting to assist with the transition to Windows Server 2008 and to help resolve the security issues raised by the audit.

Case 1: Password Security

Inadequate password security is one of the areas that the auditors believe needs improvement. The audits raised the following concerns:
1 Some bank employees have used the same user account password for several years.
2 Many of the existing passwords are only four or five characters in length.
3 Several bank employees regularly change their passwords, but rotate between the same three or four passwords with each change.
4 An employee who has forgotten a password can keep trying different combinations for as long as they like, until they hit upon the password or give up trying.
What capabilities in Windows Server 2008 enable the bank to address the auditors’ concerns? Create a short report of your recommendations for the bank’s Audit Response Committee. Also, for the IT manager who is a committee member, note what tool can be used to implement your recommendations.

Case 2: Using Windows Server 2008 Auditing

The Audit Response Committee would like to know in what ways Windows Server 2008 can provide audit information, because no auditing is currently in use. The committee would like you to create a report that provides examples of what can be audited. Also, the IT director wants you to create a set of general instructions for how to set up auditing changes to files.

Case 3: Managing Client Computers

The auditors would like to see more standardization of each user’s desktop and curtail the ability to change some important settings. Specifically they would like to:

? Prevent Windows XP and Vista clients from using Control Panel after computers have been set up.
? Ensure that all Windows XP and Vista clients start the most recent version of Microsoft Excel when they click on a file with an .xls extension.
? Prevent users from changing information about their network connections.
? Remove the My Music icon from the Start menu.

For any of these that are possible, include general instructions for the IT Department about how to implement them.

Case 4: Solving a Problem with Security Updates

The bank auditors have mentioned in several places in the audit that the network is only as secure as its weakest link. One of their concerns is that many users never take the time to update their computers as a way to apply the latest security patches. They consider regular client computer updates to be as vital as applying regular operating system updates on the bank’s servers. What Windows Server 2008 capability can address this concern? Create a report for the Audit Response Committee with your recommendations and include a brief description of any security features that accompany the capability you discuss.