There are various different types of security protocols and encryption algorithms available today. Modern techniques like DES, block cipher algorithm, public key encryption and other authentication methods are used to protect the data network to avoid the attacks from unwanted sources. To protect the secrecy of the information being transmitted, it is required to encrypt their data while transmission is occurring. To encrypt the data some sort of algorithms or protocols are necessary. To design a secure and reliable protocol is what we going to do in this project. 

PROJECT AIMS:

Construct a new type of protocol and compare its efficiency and strength with other available methods. 

RESEARH TASKS:

In depth research of the DES, RSA, Hash authentication, PGP, and other methods, and find the strength or weakness in each of them, and use the result in implementation of a new algorithm. 

The main purpose of this project is to determine the geographical position of a GSM for the purpose of discovering "black spots" and "hot spots" in Telstra’s GSM network. By using the Cell ID (CI), Timing Advance (TA) and Received Power Levels (MsRxLev) already available within Telstra’s mobile network and obtainable through DCAP, it is hoped that the position of a mobile phone can be determined up to 500m RMS, and a black spot / hot spot to an accuracy of 100m RMS. 

OBJECTIVES:

The project will be conducted with two main objectives. The first objective aims to complete the project so that it will satisfy all thesis requirements. The second is to complete and implement the project within the operational department of Telstra Mobile Networks. 
 

Mobility management enables telecommunications networks to locate roaming mobile terminals (MTs) for call delivery, and maintain connections with MTs that change their point of attachment. The wireless network consists of many small service regions called cells. Each cell is served by a base station (BS) that assigns radio frequencies, or channels, to each MT within the cell. Location management tracks and locates the MT for the delivery of incoming calls, while handoff (or handover) management allows a call in progress to continue as the MT changes channels or moves between cells. In location management, the MT periodically performs location registration, to explicitly notify the network of its new access point and store changes to its user location profile. Then, when incoming calls arrive, the network performs call delivery by querying the user profile to deliver the calls to the current cell location of the MT. Location management protocols deal with querying and storing information in location databases and sending paging signals to locate the user within the network. As a result, many of the issues are not protocol-dependent and can be applied to any of the mobile networks. 

In this project, we will search through different techniques of mobility management used in wireless networks and examine probabilistic and statistic nature of the mobility of MTs in the system. Effects of such mobility on performance of the system will be evaluated by computer simulation. The project requires a students with strong knowledge in communications, probability and stochastic process, and programming with C language. 

Wireless networks consist of many small service regions called cells. Each cell is served by a base station (BS) that assigns radio frequencies, or channels, to each mobile terminal (MT) within the cell. Different from fixed communications systems, in a wireless system, e.g. a cellular system, MTs may move around with different speed, as a pedestrian with low speed or in a car or in a train with much higher speeds. Also sometimes there is a special event in one part of a city within the cellular network coverage area. Such issues involve the wireless network designer to consider several traffic factors when assigning the limited number of channels to each BS. 

In this project, we will model the traffic of the MTs in a specific wireless network. In our model different types of traffic including voice, data, video traffics will be considered. The model will describe the probabilistic nature of changes in traffic both the traffic loads and the traffic types as a function of time. Then the model will be used to evaluate the performance of the system and that how it will be affected by the changes in traffic. Specifically, the influence of hot spot zones and sparse traffic zones will be examined. Some methods in order to balancing the traffic between adjacent cells will also be examined. 

The project requires a student with good background in communications subjects and probability. Good programming skills in C language is also required. 

One important issue in a network is the flow control which for example performed in the data link layer of the OSI reference model. The purpose of the flow control mechanism is to solve the incompatibility of the speed of transmission from a fast sender to a slow receiver. This situation can easily occur when the sender is running on a fast or lightly loaded computer and the receiver is running on a slow or heavily loaded machine. The sender keeps pumping the frames out at a high rate until the receiver is completely swamped. Even if the transmission is error free, at a certain point the receiver will simply not be able to handle the frames as they arrive and will start to lose some. 

The usual solution is to introduce flow control to throttle the sender into sending no faster than the receiver can handle the traffic. This throttling generally requires some kind of feedback mechanism, so the sender can be made aware of whether or not the receiver is able to keep up. Various flow control schemes are known, but most of them use the same basic principle. The protocol contains well-defined rules about when a sender may transmit the next frame. These rules often prohibit frames from being sent until the receiver has granted permission, either implicitly or explicitly. 

The flow control mechanisms can be categorized into stop-and-wait protocols and sliding window protocols. In this project, we develop an experimental simulation package that can show very simply to the students of Data Communication Network course what will happen in a real network if the flow control mechanism is not applied or applied but does not work properly. The project requires good background in data communication network and high-level language programming. 

Mobile satellite systems and especially low earth orbit (LEO) satellites are the promising candidates for providing personal communication services using small hand-held terminals due to their low propagation delay and loss compared to geostationary satellites. The current exponential increase in the number of subscribers of cellular mobile telephones around the world and the trends of providing new multimedia and integrated services to individuals are some of evidences to the fact that there would be a huge number of people accessing to the global satellite communications system in the near future. Therefore, there will be a requirement of having an effective and powerful multiple access scheme that manage the access of users to the limited channel resources. 

In this project, we will study different alternatives for the multiple access scheme for LEO satellite systems and compare their advantages and disadvantages regarding special characteristics of the LEO satellite systems. Because of very different characteristics of mobile satellites compared to geostationary satellites, the reasons that one scheme for example can be good for one system but not for the other one will be studied. The project requires a student with good background in communications and programming skills in order to develop simulation programs. 

Asynchronous transfer mode (ATM) is an international networking standard designed for cost-effective transfer of multimedia traffic, such as video-on-demand and video conferencing. Various ATM switch architectures have been proposed and studied extensively in order to provide high performance packet switching for integrated ATM transport. In an input-buffered packet switch, due to the head-of-line (HOL) blocking phenomenon, the maximum throughput is limited to 58.6% under uniformly distributed traffic condition. The HOL problem means that a packet can be held up by another packet ahead of it in line that is destined to a different output. If the traffic is correlated, the throughput can be even lower. To solve the problem of HOL, many queuing and scheduling techniques have been proposed in order to maximize throughput and minimize mean packet delay. These techniques are: (1) examining the first packets in a FIFO queue instead of the HOL packet only such that the HOL blocking can be alleviated; (2) maintaining a separate queue for each output such that the HOL blocking can be eliminated; and (3) using different scheduling algorithms for maximizing the throughput, such as using neural networks or heuristic algorithms. 

In this project, we discuss and compare these techniques and propose new methods for maximizing the throughput, while maintaining the packet delay at an acceptable level. The project requires a student with good background in data communications and programming skills. 

To investigate network performance issues such as scalability, availability, recoverability, etc. in the SITA Network, on high speed networks such as ATM, Frame Relay, and IPNet. SITA uses NORTEL passport and NORTEL DPN Equipment which are connected together by different PTT Carriers worldwide.

To suggest ways on how to improve the network in areas which it seems degraded. This will require monitoring and obtaining results on utilization levels of network links. To study the traffic flow through the network and the routing it takes.

Each patient who uses a cochlea implant requires their own unique 'map' which is a set of parameters installed in an external unit called a speech processor. This device supplies power to the implant and provides stimulation level data based on the patient's map. The formulation of a patient's map must be done under clinical situations and the procedure takes approximately two hours. This can be a problem with young children (less than 3 years), as the procedure requires that the patient and speech processor be tethered to the programming system throughout the procedure. 

OBJECTIVES:

The aim of this project is to develop wireless extensions to the current programming system to reduce the physical constraints imposed on young patients. The system must be safe and must reliably deal with normal transmission problems and the possibility of multiple units working in the same vicinity. The development of the system must also take into consideration the possible international spectrum restrictions placed on a product of this type. 
 

ABR provides a mechanism for dynamic allocation of available bandwidth equitably among ATM network users.  In many respects, ABR represents a best-of-both-worlds offering for applications such as Web services because it accommodates varying traffic profiles without being a bandwidth hog. 

ABR operates as a feedback mechanism that utilizes special ATM cells,  called Resource Management (RM) cells.  The feedback mechanism have been typically either binary or calculating the explicit rate and sending this information to the source through RM-cell.  Explanation of various schemes as given in ATM Forum's Traffice Management Specification version4.0. 

In this project, simulation study is to be carried out to implement one of the algorithms using OPNET to highlight the merit of the scheme being implemented.  Knowledge of C/C++ would be essential. 

Unspecified Bit Rate (UBR) traffic is designed for those data applications that want to use any left-over capacity and are not sensitive to cell loss or delay.  Such connections are not rejected on the basis of bandwidth shortage and not policed for their usage behaviour. 

One of the methods applied to minimise cell loss is Early Packet Discard (EPD) which is VC-based congestion control scheme.  ATM switch has a table for VC switching and/or VP switching. 

In this project, a simulation study is to be carried out to understand the effect of Early Packet Discard and also simulate for small and large latency configurations with varying buffer sizes and number of sources.  Simulation could be done using either YATS or OPNET and having knowledge of C/C++ would be essential. 

Demand for high-speed network has led to the development of ATM technology which has integrated voice, video, image and data to flow through a single pipe.  Because of the bottleneck in legacy LAN, high-ended server needs to be connected to high-speed network such as ATM to support the work-stations for Graphic User Interface (GUI) like netscape. 

Traditionally, ethernet adapter running at 10Mbps has a buffer memory of 8kB and because of the adapter design work-station is slow to respond to the user's demand.  One of the solutions would be to have ATM connectivity with high bandwidth for the work-stations.  Recently, ATM adapters are available at reseanable price which makes it possible to be used in pcs. 

In this project you are expected to work on the driver software for ATM adapter running on linux, to make an assigned work-station which has ATM client card to connect to the ATM switch.  ATM driver on linux at present is in its development stage and accordingly linux kernel is being updated to minimise bugs with ATM driver. 

In the second stage of the experiment would be to compare the throughput of TCP with or without end-to-end ATM/ABR service within the shared bandwidth.  Knowledge of gcc is essential and understanding of TCP/IP and ATM protocol is highly regarded.