CS403 - Database Management Systems Assignment No 2 Solution and Discussion Spring 2014 Due Date: May 26, 2014

Database Management System (CS403)

Assignment No.2 (Graded)



Total Marks: 15

Deadline:  26th May, 2014

                              

Please carefully read the following instructions before attempting the assignment.



Deadline

Your assignment must be uploaded on or before 26th May 2014.



Rules for Marking

It should be clear that your assignment will not get any credit if:

1. The assignment is submitted after due date

2. The assignment is copied

3. You are supposed to submit your assignment in .doc / Docx format. Any other formats like scan  images, PDF, Zip, rar, bmp etc will not be accepted.



For any query please contact: CS403@vu.edu.pk



Objectives

The objectives of this assignment are,

Giving the idea of a most commonly used semantic data model for graphical representation of conceptual database design i.e. Entity Relationship Data model. 
Giving the idea of entities and their attributes, cardinalities and the relationship between them.
Providing an understanding of types of relationships i.e. in how many ways an entity interact with other entity in real world.


Important Note:



This Assignment is the continuation of First Assignment. Take same case study given in Assignment 1 (also provided at the end of this assignment); apply the techniques and methods from lectures (7-13) in order to finalize the tasks of second assignment listed below in task description. 

Reference:

Please refer to the case study given in assignment no. 1 as well as to the solution of assignment 1.

Note: Same case study is also given at the end of this assignment for your convenience.

Task:

In this assignment you will focus on the task given below:

Draw a comprehensive ER-diagram along with their relationships and cardinalities.

You have to perform all the necessary steps that are included in the above task in your solution file.



Drawing Final ER Data Model:

You can use any tool for drawing like MS Office or Visio.



Important things to consider: 

As happens in real world that everyone visualize a problem in different way so the solutions of all students should be according to their own thinking not taken from some source.
As this is your first comprehensive design, so you have to work very keenly and with concentration. This design requires your full attention as this conceptual design will be transformed into a relational model in next assignment. Any mistake in this conceptual design can cause you much burden afterwards.






Case Study



Suppose we have a wireless ad hoc network. A wireless ad hoc network is a decentralized type of wireless network. The network is ad hoc because it does not rely on a pre existing infrastructure, such as routers in wired networks or access points in managed (infrastructure) wireless networks. Instead, each node participates in routing by forwarding data for other nodes, so the determination of which nodes forward data is made dynamically on the basis of network connectivity.

Nodes in the ad hoc network has unique id that identify it across the network. Each of the nodes uses a certain protocol.

Various protocols are used including aodv, dsdv, dsr etc. There are various version of a specific protocol. An ad hoc network typically refers to any set of networks where all devices have equal status on a network and are free to associate with any other ad hoc network device in link range.

Nodes in the ad hoc networks send packets to each other. Each packet has two parts namely: header and data. Header information contains source destination address and some other information. Each packet is sent on one of the route based on the source destination address. There can be several hopes around one route. Every route is assigned a weight based on some pre defined rule.