re- write the assignment

Acknowledgment

This assignment couldn’t have been completed without the assistance and effort of many people. All the support and contribution that was provided is very much valued and appreciated by our group. The completion and finishing of the assignment couldn’t have been possible without the big role played by the guidance and encouragement given to us. Our group would love to express its deepest appreciation and recognition to everyone who made this assignment reach the highest levels of success.

We would love to take this chance to show our huge appreciation to Mr Mansoor for the role he played in providing the required support and assistance to us and for showing willingness to use his free time to provide us with feedback. We would also like to thank all the lab staff in PC Lab 2 for letting us use the lab when its free.

We would also want to express our deepest gratitude to our classmates, relatives, and all family members for the moral support they have provided us with.

Abstract

In this assignment, a critical evaluation and analysis will be carried out based on the Quality of Service (QoS) of a Wide Area Network (WAN) with the help of the simulation software Riverbed Modeler. to study the network parameters, a network model should be developed first. When the network model is created, an analysis of the network will be done through comparing and contrasting different simulation outputs. After that, the network will be further improved to minimize the delay as well as errors and to improve the traffic handling. In Addition, different scenarios will be created to ensure having a network that is able to handle traffic with no delay at the lowest cost possible. Each scenario will have different capabilities and parameters, therefore each scenario will be critically evaluated, studied and analysed. Finally, an understandable comparison between scenarios will be carried out in the results followed by a well delivered conclusion.

Chapter1 Introduction

The Aim of the assignment is to determine the quality of service performance and evaluation of WAN of Al Shifa L.L.C pharmaceutical Destitution Company in Oman operating in Muscat , Dubai and Salalah . The head quarter in Muscat and a branch in Sur by integrating the concepts learned in the modeling and simulation methodology.

The objectives of the assignment are:

· Study the parameters by developing conceptual model of complex computer network.

· The network model will be created by the simulation tools.

· The output is based on analysis and configuration of the network model.

· Analysis the result that will be carried out

· Documentation of the whole work

· Drawing the conclusion from the result

· Recommendation to prevent the problems

The approach to determine the quality of service performance and evaluation of WAN of Al Shifa pharmaceutical Destitution Company broken down into five steps starting with:

i. Formulation of the problem

Al Shifa pharmaceutical Destitution Company wants to introduce real-time applications in their branches – Muscat ,dubai and salalah – such as video conferencing and VoIP to all the employees.

ii. Modelling:

In this phase the model is made and the following factors must be considered

· Accuracy of the model and the features

· Acceptability of the model in its presentation phase

· Speed and level of the detail involved

· Collection of the data and accurate simulation

· Verification of the model and management confirmation

iii. Programing:

Consider the packages to be used and the type of programming to be used and to compeer the result obtained from the model. Implementing solving and developing the conceptual model of complex computer network by using the riverbed modeler academic – edition17.5 – software program which is includes tools for study, model design, simulation, data collection, and data analysis.

iv. Experimentation:

The testing phase of the model at this stage is done, and a base run will be made to see the behavior of the system. And comparison of the results will be made in stages and for several times until the wanted result is seen in addition, sensitivity analysis helps to figure out the issues so it can be fixed.

v. Implementation

Al Shifa Company has option to implementing the idea or not.

Chapter 2: Network Model with Details Of Setup And Configuration

A WAN of alshifa LLC is designed using the riverbed software. The company consists of one headquarter in Muscat and 2 branches in Salalah and Dubai. Three fixed subnets are added which represent the company headquarter in Muscat and branches in Salalah and Dubai. All three locations provide four different applications, Web, Email, Print and FTP. Application definition is added to the network and is configured in order for the applications to be supported. And to support these selected applications, profile configuration is added and configured to the network. Profile configuration is also added in both branches to support the selected applications. Figure 2.1 shows the headquarter and two branches:

Figure 2.1 Network Model

In the headquarter, 15 clients are added that have attributes allowing them to use various applications like Web, Print, Email, and FTP. All the workstations added are connected to an ethernet32switch using a 100BaseT link. Ethernet 32 switch is selected over Ethernet 16 switch is because Ethernet 16 switch wouldn’t be sufficient for the headquarter as there are 15 workstations as well as servers and a router connected to the switch. 100baset links are used because using 10base links wouldn’t be sufficient to carry all the data and using 1000base links would cost more and provide more unused bandwidth, thus the 100 baseT link is used. Additionally, a ppp server is added to the headquarter, it is the server node which has server applications. A single Ethernet4_slip8 gateway is added and connected the Ethernet32 switch with the use of 100baseT link. Figure 2.2 shows the Headquarter:

Figure 2.2 Headquarter model

Salalah and Dubai branches are created with the similar network structure of that in headquarter. However, only 10 workstations are added in each branch with attributes to do applications like FTP, Print, Web, and Email. The clients in both branches are connected to an Ethernet 16 switch using 100base t links. After that, the Ethernet16 switch is connected to Salalah Ethernet4_slip8 gateway using a 100Base T link. Same thing is repeated again in the Dubai branch. The configuration of Salalah/Dubai branches is shown in figure 2.3:

Figure 2.3 Salalah/Dubai branch

A duplicate of the previous scenario is made to modify the network and make it support real time applications which are VoIP and video conferencing. First, the application definition node is configured by adding video conferencing with low resolution and VoIP of GSM quality speech in the application definition. However, to support these 2 applications, two profiles should be added in profile configuration, the first profile being VoIP and the second one being video conferencing. In the headquarter 2 workstations were added, one VoIP and one video conferencing as shown in figure 2.4:

Figure 2.4 Voice and Video

Figure 2.5 demonstrates the second scenario of Salalah branch, where two clients are added that support video conferencing and VoIP

Figure 2.5 Salalah/Dubai with Voice and Video

Scenario 3 is then created by duplicating scenario 2. In scenario 3, after VoIP and video conferencing were added to the network, delay was observed in the network. And since delay is not tolerated when it comes to real time applications because they are time-sensitive applications, QoS was introduced to combat the delay. To introduce QoS to the network, the QoS node should be first added to the network. After its added, the First-In-First-Out (FIFO) method is applied to the PPP DS1 links interconnecting the headquarter and braches to minimize delay as shown in figure 2.6.

Figure 2.6 QoS applied to the network

Scenario 4 and 5 are created by duplicating scenario 2 again. The same mechanism applied in scenario 3 is applied in scenario 4, the only difference is that in scenario 4 the queuing method is Weighted Fair Queuing (WFQ) and in scenario 5 the queuing method is Priority Queuing (PQ) which is applied to the PPP DS1 links interconnecting the headquarter and offices.

Chapter 3: Results and Analysis

To analyse the results of ALSHIFA LLC network, selection of many statistics was done. These statics included the traffic sent (bytes/sec) of Email, Print, Web and FTP. Moreover, other statics were also considered such as the throughput and utilization for all the applications in the network using the DDD DS1 links going from Dubai to Muscat or from Salalah to Muscat. For real time applications, other statics have been selected to be analysed. In video conferencing, packet end-to-end delay as well as packet delay variation were observed. In voice, packet end-to-end delay, jitter and packet delay variation statics were selected. The duration of the simulation was 5 minutes for all the scenarios.

4.1 Conclusion

The Aim of the assignment is to determine the quality of service performance and evaluation of WAN of Al Shifa Company in Oman operating in Muscat , DUBAI AND SALALH. The head quarter in Muscat and a branch in dubai and salalah by integrating the concepts learned in the modeling and simulation methodology. The objectives of the assignment are study the parameters by developing conceptual model of complex computer network. And network model will be created by the simulation tools. In addition, output is based on analysis and configuration of the network model. As well as analysis of the result that will be carried out then documentation of the whole work. Conclude with, drawing the conclusion from the result and writ recommendations to prevent the problems.

From the result obtained after configuring the real-time applications in Al Shifa Company network for all branches, the company is not capable of supporting real-time multimedia service such as Video conferencing and VoIP services to all consumers between the two branches. As telecommunication engineers who study simulating multimedia networks, to solve the problem in configuring the real-time applications such as Video conferencing and VoIP services in Al Shifa Company network it will be improved the quality of service (QoS) by using Weighted Fair Queuing (WFQ).

WFQ improve the multimedia service in Al Shifa Company network. In addition, the average of voice packet end-to-end delay decreases 10 phases. Furthermore, the WFQ improve the multimedia service in Al Shifa Company network. In addition, the average of voice packet delay variation decreases 35 phases.

4.1 Recommendations

The company can improve the QoS of their network by:

· A network monitoring system: Target the QoS at a network interface by using server or router’s performance.

· Give more bandwidth to the important Packets to transfer first.

· Evolved connectivity from 100Base-T to Gigabit Ethernet. However, this speed requires a significant investment.

· Improving Network efficiency via IPQoS.