Orthogonal variable spreading factor (OVSF) code is used in WCDMA system to provide variable service data rates. However, most researches focus on decreasing the number of code assignment without considering how to manage bandwidth with properties of OVSF code. In this research, we propose a dynamic bandwidth borrowing algorithm for quality of service (QoS) supported in the OVSF-CDMA system. When a new call arrives or a current serviced call requests a higher data rate, but the system can not provide the required bandwidth, the borrowing algorithm can be activated to borrow bandwidth from current serviced calls. Also, a dynamic bandwidth reserved algorithm is proposed to avoid forced termination caused by the suddenly increasing bandwidth requirements of current serviced calls. Simulation results show that the value of throughput increases and the QoS of current serviced calls can be maintained.

Broadband Wireless Access Systems (BWASs) such as High Speed Downlink Packet Access (HSDPA) and the Worldwide Interoperability for Microwave Access (WiMAX), pose a myriad of new opportunities for leveraging the support of a wide range of “content-rich” mobile multimedia services with diverse Quality of Service (QoS) requirements. This is due to the remarkably high bandwidth that is supported by these systems, which was previously only available to wireline connections. Despite the support for such high bandwidth, satisfying the diverse QoS of users while maximizing the revenues of network operators is still one of the major issues in these systems. Bandwidth management, therefore, will play a decisive role in the success of such wireless access systems. Without efficient bandwidth management, network operators may not be able to meet the growing demand of users for multimedia services, and may consequently suffer great revenue loss. Bandwidth management in BWASs is, however, a challenging problem due to many issues that need to be taken into consideration. Examples of such issues include the diverse QoS requirements of the services that BWASs support, the varying channel quality conditions of mobile users, and hence the varying amount of resources that are needed to guarantee certain QoS levels during the lifetime of user connections, the utilization of shared channels for data delivery instead of dedicated ones and network congestion. In this thesis, we address the problem of bandwidth management in BWASs and propose efficient economic-based solutions in order to deal with these issues at different bandwidth management levels, and hence enhance the QoS support in these systems. Specifically, we propose a bandwidth management framework for BWASs. The framework is designed to support multiple classes of traffic with different users having different QoS requirements, maximize the throughput of BWASs, support inter- and intra-class fairness, prevent network congestion and maximize the network operator’s revenues. The framework consists of three related components, namely packet scheduling, bandwidth provisioning and Call Admission Control-based dynamic pricing. By efficiently managing the wireless bandwidth prior to users’ admission (i.e.,pre-admission bandwidth management) and during the users’ connections (i.e., post-admission bandwidth management), these schemes are shown to achieve the design goals of our framework. / Thesis (Ph.D, Computing) -- Queen's University, 2009-04-01 15:35:36.213

Application adaptive bandwidth management is a strategy for ensuring secure and reliable network operation in the presence of undesirable applications competing for a network’s crucial bandwidth, covert channels of communication via non-standard traffic on well-known ports, and coordinated Denial of Service attacks. The study undertaken here explored the classification, analysis and management of the network traffic on the basis of ports and protocols used, type of applications, traffic direction and flow rates on the East Tennessee State University’s campus-wide network. Bandwidth measurements over a nine-month period indicated bandwidth abuse of less than 0.0001% of total network bandwidth. The conclusion suggests the use of the defense-in-depth approach in conjunction with the KHYATI (Knowledge, Host hardening, Yauld monitoring, Analysis, Tools and Implementation) paradigm to ensure effective information assurance.

Made available in DSpace on 2016-04-04T18:31:32Z (GMT). No. of bitstreams: 1 Aturo Jose Fenile Peris.pdf: 4348655 bytes, checksum: 34479e7af136c0f06a1b46d21b30c1c4 (MD5) Previous issue date: 2012-06-22 / The design of the IEEE 802.11 standard allows, in certain situations, competition for access to the transmission medium results in an anomaly. As a result of this anomaly, mobile stations that should achieve high rates of transmission are impaired and don t get those rates. The consequence is the transmission capacity low utilization of the wireless system and the natural increasing of the time mobile stations stays on (and consuming energy); because of this, the increase in energy consumption is another effect of this anomaly. From this scenario, one way to deal with this anomaly is to have a better utilization of the wireless transmission medium. In this context, this work proposes a bench for studies of flow control in IEEE 802.11; this bench allows the management of bandwidth and the collection of traffic statistics from users sessions connected to the wireless network. As a resulting study from the bench using, there is a proposal to mitigate the anomaly through the user traffic management. The results indicate that the controlling the traffic from users who are in poor wireless transmission may produce a better utilization of transmission capacity of an IEEE 802.11 access point. / A concep??o do padr?o IEEE 802.11 permite que, em determinadas situa??es, a competi??o pelo acesso ao meio de transmiss?o resulte em uma anomalia. Como resultado dessa anomalia, esta??es m?veis que deveriam conseguir altas taxas de transmiss?o s?o prejudicadas e acabam por n?o conseguir essas taxas. A consequ?ncia ? o baixo aproveitamento da capacidade de transmiss?o do sistema sem fio e o natural aumento do tempo em que as esta??es m?veis permanecem ligadas e consumindo energia; por conta disso, o aumento no consumo de energia ? outro efeito dessa anomalia. A partir desse cen?rio, uma forma de combater essa anomalia ? a melhoria da utiliza??o do meio de transmiss?o sem fio. Nesse contexto, este trabalho apresenta uma proposta de bancada para estudos de controle de vaz?o em redes IEEE 802.11; essa bancada permite gerenciar a largura de banda e coletar dados estat?sticos relativos ao tr?fego das sess?es dos usu?rios conectados ? rede sem fio. Como estudo resultante da utiliza??o da bancada, h? uma proposta de mitiga??o da anomalia por meio da gest?o do tr?fego dos usu?rios. Os resultados indicam que o controle do tr?fego de usu?rios que est?o em m?s condi??es de transmiss?o sem fio pode melhorar o aproveitamento da capacidade de transmiss?o de um ponto de acesso IEEE 802.11.

The aim of this thesis project is to explore a network traffic regulator using bandwidth management techniques that regulates data traffic with the objective to use the network bandwidth to its maximum capacity while ensuring that the network is not overloaded. The bandwidth in the existing network architecture is shared between two co-existing, distinct data flows for on-board communication and diagnostic communication in an in-vehicle network. The diagnostic communication must not interfere with the more critical on-board communication and it should comply with the remaining bandwidth. In the existing solution, fixed delays are imposed on the data traffic which result in a waste of network capacity. The approach presented in this thesis uses two regulation algorithms for different types of diagnostic services. One regulation algorithm is activated for diagnostic services that require data segmentation and multiple data frames to accommodate the transferred data. This algorithm makes use of the Flow Control parameter Separation Time specified in ISO 15765-1:2011 "Road vehicles -- Diagnostic communication over Controller Area Network (DoCAN)". The other algorithm regulates diagnostic services that generate bursts of single frames where data segmentation is not required and it does so using traffic shaping techniques. The results in this thesis show that the network traffic indeed can be regulated for different diagnostic services by using the two mentioned regulation algorithms. The results also show that data is not lost due to high network utilisation and that the bandwidth is used to its maximum capacity without having to impose fixed delays on the network system. The regulator is adaptive in the sense that it can be used for different vehicle configurations with compatible network systems to ensure quality of service and a robust network system. / I detta examensarbete är målet att utforska en metod för att reglera  nätverkstrafik genom att använda tekniker inom bandbreddshantering  med syfte att utnyttja bandbredden till dess maximala kapacitet utan att överbelasta nätverket. Bandbredden i den nuvarande nätverksarkitekturen delas mellan två dataflöden för onboard kommunikation och diagnostisk kommunikation. Den diagnostiska kommunikationen får inte på någotvis störa onboard kommunkationen och får anpassa sig till den bandbredd som kvarstår. I det existerande systemet införs fixa fördröjningar i nätverkstrafiken vilket medför ett onödigt slöseri på nätverkskapaciteten och som också medför att de diagnostiska tjänsterna tar längre tid att utföra.  Tillvägagångssättet som presenteras i detta arbete använder två regleringsalgoritmer för olika typer av diagnostiska tjänster. En algoritm används för tjänster som kräver datasegmentering och flera dataramar för att skicka data. Den här algoritmen använder parametern Separation Time som är specificerad i ISO standarden 15765-1:2011 "Road vehicles -- Diagnostic communication over Controller Area Network (DoCAN)". Diagnostiska tjänster som istället genererar en skur av enstaka dataramar regleras med en traffic shaping algoritm som heter Token Bucket. Resultaten i detta arbete visar att det går att reglera nätverkstrafiken för olika typer av diagnostiska tjänster genom att använda de två utvecklade algoritmerna. Resultaten visar också att data inte går förlorat vid höga nätverkslaster och att bandbredden används maximalt utan att behöva införa fixa fördröjningar i nätverkssystemet. Regleraren är adaptiv i bemärkelsen att den kan användas för alla tänkbara fordonskonfigurationer med kompatibelt nätverkssystem för att försäkra quality of service och robusthet.

No / Fairness in bandwidth resource allocation is highly significance to the advancement of the future generation mobile and wireless technologies. It is likely that restriction of bandwidth due to the employment of some scheduling scheme would not be an appropriate option for the future development of communication systems. However, there is need to consider an implementation that would lead to good network performance and avoid unguaranteed bandwidth delivery. This paper focusses on evaluating the performance of Bandwidth Allocation using Dynamic Label Switching Paths (LSPs) Tunnelling and Label Distribution Protocol (LDP) signalling in Multi-Protocol Label Switching (MPLS) network. This will make provision for bandwidth allocation and reservation possible. An appropriate bandwidth allocation would have a positive impact on throughput as well as the delay. The results of an IP (Internet Protocol) Network without MPLS enabled is compared with MPLS model network. Furthermore, implementation of dynamic and static LSPs models are presented with about 75% decrease in packet delay variation for dynamic LSP when compared from static LSP. In addition, the models of bandwidth estimation, bandwidth allocation, delay and jitter are provided. Performance metrics used in this respect for multimedia services (Voice and Video conferencing) confirm that the modified models are improved in comparison with the baseline, having highest throughput of about 51% increment, and packet delay variation decreases drastically.

The Transmission Control Protocol (TCP) is the dominant transport protocol in today?s Internet. The original design of TCP left congestion control open to future designers. Short of implementing changes to the TCP stack on the end-nodes themselves, Internet Service Providers have employed several techniques to be able to operate their network equipment efficiently. These techniques amount to shaping traffic to reduce cost and improve overall customer satisfaction. <br /><br /> The method that gives maximum control when performing traffic shaping is using an inline traffic shaper. An inline traffic shaper sits in the middle of any flow, allowing packets to pass through it and, with policy-limited freedom, inspects and modifies all packets as it pleases. However, a number of practical issues such as hardware reliability or ISP policy, may prevent such a solution from being employed. For example, an ISP that does not fully trust the quality of the traffic shaper would not want such a product to be placed in-line with its equipment, as it places a significant threat to its business. What is required in such cases is third-party rate control. <br /><br /> Formally defined, a third-party rate controller is one that can see all traffic and inject new traffic into the network, but cannot remove or modify existing network packets. Given these restrictions, we present and study a technique to control TCP flows, namely triple-ACK duplication. The triple-ACK algorithm allows significant capabilities to a third-party traffic shaper. We provide an analytical justification for why this technique works under ideal conditions and demonstrate via simulation the bandwidth reduction achieved. When judiciously applied, the triple-ACK duplication technique produces minimal badput, while producing significant reductions in bandwidth consumption under ideal conditions. Based on a brief study, we show that our algorithm is able to selectively throttle one flow while allowing another to gain in bandwidth.

The Transmission Control Protocol (TCP) is the dominant transport protocol in today?s Internet. The original design of TCP left congestion control open to future designers. Short of implementing changes to the TCP stack on the end-nodes themselves, Internet Service Providers have employed several techniques to be able to operate their network equipment efficiently. These techniques amount to shaping traffic to reduce cost and improve overall customer satisfaction. <br /><br /> The method that gives maximum control when performing traffic shaping is using an inline traffic shaper. An inline traffic shaper sits in the middle of any flow, allowing packets to pass through it and, with policy-limited freedom, inspects and modifies all packets as it pleases. However, a number of practical issues such as hardware reliability or ISP policy, may prevent such a solution from being employed. For example, an ISP that does not fully trust the quality of the traffic shaper would not want such a product to be placed in-line with its equipment, as it places a significant threat to its business. What is required in such cases is third-party rate control. <br /><br /> Formally defined, a third-party rate controller is one that can see all traffic and inject new traffic into the network, but cannot remove or modify existing network packets. Given these restrictions, we present and study a technique to control TCP flows, namely triple-ACK duplication. The triple-ACK algorithm allows significant capabilities to a third-party traffic shaper. We provide an analytical justification for why this technique works under ideal conditions and demonstrate via simulation the bandwidth reduction achieved. When judiciously applied, the triple-ACK duplication technique produces minimal badput, while producing significant reductions in bandwidth consumption under ideal conditions. Based on a brief study, we show that our algorithm is able to selectively throttle one flow while allowing another to gain in bandwidth.

Hybrid Wireless Networks (HWNs) are composite networks comprises of different technologies, possibly with overlapping coverage. Users with multimode terminals in HWNs are able to initiate connectivity that best suits their attributes and the requirements of their applications. There are many complexities in hybrid wireless networks due to changing data rates, frequency of operation, resource availability, QoS and also, complexities in terms of mobility management across different technologies. A superstore is a very large retail store that serves as a one-stop shopping destination by offering a wide variety of goods that range from groceries to appliances. It provide all types services such as banking, photo center, catering, etc. The good examples of superstores are: Tesco (hypermarkets, United Kingdom), Carrefour(hypermarkets, France), etc. Generally, the mobile customer communicates with superstore server using a transaction. A transaction corresponds to a finite number of interactive processes between the customer and superstore server. A few superstore transactions, examples are, product browsing, Technical details inquiry, Financial transactions, billing, etc. This thesis aims to design and develop the following schemes to solve some of the above indicated problems of a hybrid wireless superstore network: 1 Transaction based bandwidth management. 2 Transaction-based resource management. 3 Transaction-based Quality of Service management. 4. Transactions-based topology management. We, herewith, present these developed schemes, the simulation carried out and results obtained, in brief. Transaction-based bandwidth management The designed Transaction-Based Bandwidth Management Scheme (TB-BMS) operates at application-level and intelligently allocates the bandwidth by monitoring the profit oriented sensitivity variations in the transactions, which are linked with various profit profiles created over type, time, and history of transactions. The scheme mainly consists of transaction classifier, bandwidth determination and transactions scheduling modules. We have deployed these scheme over a downlink of HWNs, since the uplink caries simple quires from customers to superstore server. The scheme uses transaction scheduling algorithm, which decides how to schedule an outgoing transaction based on its priority with efficient use of available BW. As we observe, not all superstore transactions can have the same profit sensitive information, data size and operation type. Therefore, we classify the superstore transactions into four levels based on profit, data size, operation type and the degree of severity of information that they are handling. The aim of transaction classification module is to find the transaction sensitivity level(TSL) for a given transaction. The bandwidth determination module estimates bandwidth requirement for each of the transactions. The transactions scheduling module schedules the transactions based on availability of bandwidth as per the TSL of the transaction. The scheme schedules the highest priority transactions first, keeping the lowest priority transaction pending. If all the highest priority transactions are over, then it continues with next priority level transactions, and so on, in every slot. We have simulated the hybrid wireless superstore network environment with WiFi and GSM technologies. We simulated four TSL levels with different bandwidth. The simulation under consideration uses different transactions with different bandwidth requirements. The performance results describe that the proposed scheme considerably improves the bandwidth utilization by reducing transaction blocking and accommodating more essential transactions at the peak time of the business. Transaction-based resource management In the next work, we have proposed the transaction-based resource management scheme (TB-RMS) to allocate the required resources among the various customer services based on priority of transactions. The scheme mainly consists of transaction classifier, resource estimation and transactions scheduling modules. This scheme also uses a downlink transaction scheduling algorithm, which decides how to schedule an outgoing transaction based on its priority with efficient use of available resources. The transaction-based resource management is similar to that of TB-BMS scheme, except that the scheme estimates the resources like buffer, bandwidth, processing time for each of transaction rather than bandwidth. The performance results indicate that the proposed TB-RMS scheme considerably improves the resource utilization by reducing transaction blocking and accommodating more essential transactions at the peak time. Transaction-based Quality of Service management In the third segment, we have proposed a police-based transaction-aware QoS management architecture for the downlink QoS management. We derive a policy for the estimation of QoS parameters, like, delay, jitter, bandwidth, transaction loss for every transaction before scheduling on the downlink. We use Policy-based Transaction QoS Management(PTQM) to achieve the transaction based QoS management. Policies are rules that govern a transaction behavior, usually implemented in the form of if(condition) then(action) policies. The QoS management scheme is fully centralized, and is based on the ideas of client-server interaction. Each mobile terminal is connected to a server via WiFi or GSM. The master policy controller (MPDF) connects to the policy controller of the WiFi network (WPDF)and the GSM policy controller(PDF). We have considered the simulation environment similar to earlier schemes. The results shows that the policy-based transaction QoS management is improves performance and utilizes network resources efficiently at the peak time of the superstore business. Transactions-Aware Topology Management(TATM) Finally, we have proposed a topology management scheme to the superstore hybrid wireless networks. A wireless topology management that manages the activities and features of a wireless network connection. It may control the process of selecting an available access points, authentication and associating to it and setting up other parameters of the wireless connection. The proposed topology management scheme consists of the transaction classifier, resource estimation module, network availability and status module and transaction-aware topology management module. The TATM scheme is to select the best network among available networks to provide transaction response(or execution). We have simulated hybrid wireless superstore network with five WiFi and two GSM technologies. The performance results indicate that the transaction-based topology management scheme utilizes the available resources efficiently and distributed transaction loads evenly in both WiFi and GSM networks based on the capacity.

Multi-Protocol Label Switching (MPLS) makes use of traffic engineering (TE) techniques and a variety of protocols to establish pre-determined highly efficient routes in Wide Area Network (WAN). Unlike IP networks in which routing decision has to be made through header analysis on a hop-by-hop basis, MPLS makes use of a short bit sequence that indicates the forwarding equivalence class (FEC) of a packet and utilises a predefined routing table to handle packets of a specific FEC type. Thus header analysis of packets is not required, resulting in lower latency. In addition, packets of similar characteristics can be routed in a consistent manner. For example, packets carrying real-time information can be routed to low latency paths across the networks. Thus the key success to MPLS is to efficiently control and distribute the bandwidth available between applications across the networks. A lot of research effort on bandwidth management in MPLS networks has already been devoted in the past. However, with the imminent roll out of 5G, MPLS is seen as a key technology for mobile backhaul. To cope with the 5G demands of rich, context aware and multimedia-based user applications, more efficient bandwidth management solutions need to be derived. This thesis focuses on the design of bandwidth management algorithms, more specifically QoS scheduling, in MPLS network for 5G mobile backhaul. The aim is to ensure the reliability and the speed of packet transfer across the network. As 5G is expected to greatly improve the user experience with innovative and high quality services, users’ perceived quality of service (QoS) needs to be taken into account when deriving such bandwidth management solutions. QoS expectation from users are often subjective and vague. Thus this thesis proposes the use of fuzzy logic based solution to provide service aware and user-centric bandwidth management in order to satisfy requirements imposed by the network and users. Unfortunately, the disadvantage of fuzzy logic is scalability since dependable fuzzy rules and membership functions increase when the complexity of being modelled increases. To resolve this issue, this thesis proposes the use of neuro-fuzzy to solicit interpretable IF-THEN rules.The algorithms are implemented and tested through NS2 and Matlab simulations. The performance of the algorithms are evaluated and compared with other conventional algorithms in terms of average throughput, delay, reliability, cost, packet loss ratio, and utilization rate. Simulation results show that the neuro-fuzzy based algorithm perform better than fuzzy and other conventional packet scheduling algorithms using IP and IP over MPLS technologies. / Tertiary Education Trust Fund (TETFUND)