Browsing by Author "Murgu, Alexandru"

Now showing 1 - 16 of 16
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    Open Access
    An adaptive SVC-video streaming scheme for mobile WiMAX networks
    (2011) Keta, Khotso Hamilton; Murgu, Alexandru
    The problem that is being addressed in this study is bandwidth fluctuation that occurs during a video stream delivery over the Mobile WiMAX network, which results in video quality degradation. To address this problem, H.264AVC/SVC coded video is used.
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    Aggregated service consolidation by multi-server virtualization
    (2012) Nkubito, Phillip Uwizeye; Murgu, Alexandru
    Virtualization is seen as the underlying technology that will make ubiquitous internet a reality by giving service providers a means to manage and consolidate their services on fewer infrastructures, while also being able to still deliver agreed service levels to their customers. Data centres have taken on server virtualization due to its benefits such as reduced operational cost, centralized administration, enhanced security, load balancing and improved hardware utilization. The resource management capabilities offered by server virtualization implies that these providers can now make use of previously redundant computing resources by aggregating them into a pool of resources. Virtual machine (VM) live migration is a core feature in resource management as it allows running applications in the VMs to be relocated to another host so as to maintain Service Level Agreements (SLAs) or for host maintenance purposes, with near zero degradation to the performance of the hosted service. However there is a need to manage optimally the live migration process especially when dealing with heterogeneous workloads such as CPU, memory and network intensive hosted applications which put a strain on different computing resources. By doing so, a service provider reaps maximum benefits from the live migration process. This study aims to optimize the live migration process during the migration of a VM running a Voice over IP (VoIP) service from a source to target host residing on the same Local Area Network. The proposed design framework focused on modifying the pre-copy algorithm which is in charge of performing the live migration. The modifications introduced a statistical dirty page tracking scheme into the algorithm and also incorporated the use of CPU scheduling to improve the performance of the live migration. A proof of concept was setup in the form of a testbed using Xen as the virtualization platform. Experiments carried out, showed that the downtime and migration time of the VoIP service were significantly reduced with minimal degradation on the call quality as perceived by the user during the live migration.
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    Open Access
    An investigation into dynamical bandwidth management and bandwidth redistribution using a pool of cooperating interfacing gateways and a packet sniffer in mobile cloud computing
    (2021) Shuuya, Lukas; Murgu, Alexandru
    Mobile communication devices are increasingly becoming an essential part of almost every aspect of our daily life. However, compared to conventional communication devices such as laptops, notebooks, and personal computers, mobile devices still lack in terms of resources such as processor, storage and network bandwidth. Mobile Cloud Computing is intended to augment the capabilities of mobile devices by moving selected workloads away from resource-limited mobile devices to resource-intensive servers hosted in the cloud. Services hosted in the cloud are accessed by mobile users on-demand via the Internet using standard thick or thin applications installed on their devices. Nowadays, users of mobile devices are no longer satisfied with best-effort service and demand QoS when accessing and using applications and services hosted in the cloud. The Internet was originally designed to provide best-effort delivery of data packets, with no guarantee on packet delivery. Quality of Service has been implemented successfully in provider and private networks since the Internet Engineering Task Force introduced the Integrated Services and Differentiated Services models. These models have their legacy but do not adequately address the Quality of Service needs in Mobile Cloud Computing where users are mobile, traffic differentiation is required per user, device or application, and packets are routed across several network domains which are independently administered. This study investigates QoS and bandwidth management in Mobile Cloud Computing and considers a scenario where a virtual test-bed made up of GNS3 network software emulator, Cisco IOS image, Wireshark packet sniffer, Solar-Putty, and Firefox web browser appliance is set up on a laptop virtualized with VMware Workstation 15 Pro. The virtual test-bed is in turn connected to the real world Internet via the host laptop's Ethernet Network Interface Card. Several virtual Firefox appliances are set up as endusers and generate traffic by launching web applications such as video streaming, file download and Internet browsing. The traffic generated by the end-users and bandwidth used is measured, monitored, and tracked using a Wireshark packet sniffer installed on all interfacing gateways that connect the end-users to the cloud. Each gateway aggregates the demand of connected hosts and delivers Quality of Service to connected users based on the Quality of Service policies and mechanisms embedded in the gateway. Analysis of the results shows that a packet sniffer deployed at a suitable point in the network can identify, measure and track traffic usage per user, device or application in real-time. The study has also demonstrated that when deployed in the gateway connecting users to the cloud, it provides network-wide monitoring and traffic statistics collected can be fed to other functional components of the gateway where a dynamical bandwidth management scheme can be applied to instantaneously allocate and redistribute bandwidth to target users as they roam around the network from one location to another. This approach is however limited and ensuring end-to-end Quality of Service requires mechanisms and policies to be extended across all network layers along the traffic path between the user and the cloud in order to guarantee a consistent treatment of traffic.
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    Open Access
    Application Aware Multicasting in VPLS Networks.
    (2012) Kweli,Allan; Murgu, Alexandru
    Enterprise customer demand for business class Ethernet service offerings, over the years, has steadily increased. More so, the demand for high throughput coupled with efficient utilization of the available bandwidth. This has driven service providers to seek more reliable means of delivering services to their customers. As businesses expand both financially and geographically service providers have deployed Wide Area Networks (WANs) to deliver Ethernet services to their customers. However the deployment of such networks raises issues related to the cost and scalability of the network deployment. Furthermore the efficiency, in relation to resource utilization, of the network is a major concern to both the SP and the client. Ethernet services provided by a Virtual Private LAN Service (VPLS) network provide scalability, resilience and efficient utilization of the existing network resources. The objectives of this thesis are to investigate how VPLS can offer on-demand business class Ethernet services while being consistent with the core network organization. Furthermore this research aims to develop efficient bandwidth utilization in a Point-to-Multipoint VPLS network using Multiprotocol Label Switching (MPLS) as a transport protocol. MPLS is a Layer 2.5 transport protocol that encapsulates and labels frames from their sources to their destinations. MPLS uses labels to identify the frame destination and in so doing reduces the overall bandwidth when IP headers are used. MPLS facilitates the deployment of VPLS networks, thus VPLS relies on MPLS as its transport protocol. VPLS networks offer emulated Ethernet services, are scalable and are not restricted by geographical dispersion of the customer sites. VPLS networks over MPLS also offer efficient utilization of the networks' bandwidth through mechanisms such as multicast awareness, auto-bandwidth allocation, signaling and auto-discovery. From the mentioned mechanisms, this thesis aims at setting up a VPLS network in a virtualized environment. The reason being, it is cost effective and line with archiving cost efficiency. In the VPLS network, the preferred signaling protocol is Label Distribution Protocol (LDP) as it is essential in the establishment of the MPLS backbone network. The VPLS pseudowires are dynamically created using the Border Gateway Protocol (BGP) protocol. The BPG protocol also ensures scalability, using route-reflect routers in the network. The auto- discovery of peering nodes in the VPLS network is achieved using the BGP protocol. Multicast vii awareness is achieved by configuring separate VPLS instances. Therefore the traffic is not flooded into the network but rather forwarded to members belonging to the same VPLS instance so the existing bandwidth is efficiently utilized. By using MPLS traffic engineered (MPLS- TE)tunnels; the auto-bandwidth mechanism is implemented. Auto-bandwidth control over the MPLS-TE tunnels ensures improved utilization of the available tunnel bandwidth. As mentioned before, the VPLS network is in a virtualized environment. The network routers are based on the Mikrotik routerOS. The routerOS is a standalone operating system based on the Linux v2.6 kernel. The customer sites created have server and client machines, all of which have been virtualized.
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    Auto-bandwidth control in dynamically reconfigured hybrid-SDN MPLS networks
    (2021) Brandt, Angus Daniel; Murgu, Alexandru
    The proposition of this work is based on the steady evolution of bandwidth demanding technology, which currently and more so in future, requires operators to use expensive infrastructure capability smartly to maximise its use in a very competitive environment. In this thesis, a traffic engineering control loop is proposed that dynamically adjusts the bandwidth and route of flows of Multi-Protocol Label Switching (MPLS) tunnels in response to changes in traffic demand. Available bandwidth is shifted to where the demand is, and where the demand requirement has dropped, unused allocated bandwidth is returned to the network. An MPLS network enhanced with Software-defined Networking (SDN) features is implemented. The technology known as hybrid SDN combines the programmability features of SDN with the robust MPLS label switched path features along with traffic engineering enhancements introduced by routing protocols such as Border Gateway Patrol-Traffic Engineering (BGP-TE) and Open Shortest Path First-Traffic Engineering (OSPF-TE). The implemented mixed-integer linear programming formulation using the minimisation of maximum link utilisation and minimum link cost objective functions, combined with the programmability of the hybrid SDN network allows for source to destination demand fluctuations. A key driver to this research is the programmability of the MPLS network, enhanced by the contributions that the SDN controller technology introduced. The centralised view of the network provides the network state information needed to drive the mathematical modelling of the network. The path computation element further enables control of the label switched path's bandwidths, which is adjusted based on current demand and optimisation method used. The hose model is used to specify a range of traffic conditions. The most important benefit of the hose model is the flexibility that is allowed in how the traffic matrix can change if the aggregate traffic demand does not exceed the hose maximum bandwidth specification. To this end, reserved hose bandwidth can now be released to the core network to service demands from other sites.
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    Data storage security for cloud computing using elliptic curve cryptography
    (University of Cape Town, 2020) Buop, George Onyango; Murgu, Alexandru
    Institutions and enterprises are moving towards more service availability, managed risk and at the same time, aim at reducing cost. Cloud Computing is a growing technology, thriving in the fields of information communication and data storage. With the proliferation of online activity, more and more information is saved as data every day. This means that more data is being stored in the cloud than ever before. Data that is stored online often holds private information – such as addresses, payment details and medical documentation. These become the target of cyber criminals. There is therefore growing need to protect these data from threats and issues such as data breach and leakage, data loss, account takeover or hijackings, among others. Cryptography refers to securing the information and communication techniques based on mathematical concepts and algorithms which transform messages in ways that are hard to decipher. Cryptography is one of the techniques we could protect data stored in the cloud as it enables security properties of data confidentiality and integrity. This research investigates the security issues that affect storage of data in the cloud. This thesis also discusses the previous research work and the currently available technology and techniques that are used for securing data in the cloud. This thesis then presents a novel scheme for security of data stored in Cloud Computing by using Elliptic Curve Integrated Encryption Scheme (ECIES) that provides for confidentiality and integrity. This scheme also uses Identity Based Cryptography (IBC) for more efficient key management. The proposed scheme combines the security of Identity- Based Cryptography (IBC), Trusted cloud (TC), and Elliptic Curve Cryptography (ECC) to reduce system complexity and provide more security for cloud computing applications. The research shows that it is possible to securely store confidential user data on a Public Cloud such as Amazon S3 or Windows Azure Storage without the need to trust the Cloud Provider and with minimal overhead in processing time. The results of implementing the proposed scheme shows faster and more efficient communication operation when it comes to key generation as well as encryption and decryption. The difference in the time taken for these operations is as a result of the use of ECC algorithm which has a small key size and hence highly efficient compared with other types of asymmetric cryptography. The results obtained show the scheme is more efficient, when compared with other classification techniques in the literature.
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    Distributed control of reconfigurable mobile network agents for resource coordination
    (2012) Ogbeide, Stanley Aiyanyor; Murgu, Alexandru
    Considering the tremendous growth of internet applications and network resource federation proposed towards future open access network (FOAN), the need to analyze the robustness of the classical signalling mechanisms across multiple network operators cannot be over-emphasized. It is envisaged, there will be additional challenges in meeting the bandwidth requirements and network management...The first objective of this project is to describe the networking environment based on the support for heterogeneity of network components...
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    NeXtRAD antenna design: X-Band dual polarised conical horn antenna
    (2016) Cheng, Po-Kai; Murgu, Alexandru; Downing, B J; Inggs, Michael
    The purpose of the dissertation is to investigate a design and implementation of a dual polarised X-band antenna. The desired specifications include a centre frequency of 8.5 GHzand a 10_ azimuth-half power beam width in both vertical and horizontal polarisations. Other requirements include peak power handling of 400 W over a 50 MHz instantaneous bandwidth and the facility to be mounted on a standard tripod. The dissertation begins by introducing NeXtRAD, a radar project developed jointly by UCL and UCT, outlines the objective of the study and lists all the requirements to be achieved. After considering several types of antenna, horn antenna has been the most practical when trying to meet project requirements. Two of the horn antennas examined here have been the square and conical horn antennas using square and circular waveguides respectively. Each of these waveguides support dual polarisation as they provide a symmetrical structure in two orthogonal planes of polarisation. The square waveguide is flared into a square horn whereas the circular waveguide is flared into a conical horn to increase the gain and reduce the half-power beamwidth to the required angle.
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    Novel approaches to performance evaluation and benchmarking for energy-efficient multicast: empirical study of coded packet wireless networks
    (2016) Ajibesin, Adeyemi Abel; Ventura, Neco; Murgu, Alexandru; Chan, H Anthony
    With the advancement of communication networks, a great number of multicast applications such as multimedia, video and audio communications have emerged. As a result, energy efficient multicast in wireless networks is becoming increasingly important in the field of Information and Communications Technology (ICT). According to the study by Gartner and Environmental Protection Agency (EPA) report presented to United State Congress in 2007,energy consumption of ICT nodes accounts for 3% of the worldwide energy supply and is responsible for 2% of the global Carbon dioxide (CO2) emission. However, several initiatives are being put in place to reduce the energy consumption of the ICT sector in general. A review of related literature reveals that existing approaches to energy efficient multicast are largely evaluated using a single metric and while the single metric is appropriate for effective performance, it is unsuitable for measuring efficiency adequately. This thesis studied existing coded packet methods for energy efficiency in ad hoc wireless networks and investigates efficiency frontier, which is the expected minimum energy within the minimum energy multicast framework. The energy efficiency performance was based on effective evaluation and there was no way an inefficient network could reach a level of being an efficiency frontier. Hence, this work looked at the position of how true efficiency evaluation is obtained when the entire network under examination attains their efficiency frontiers using ratios of weighted outputs to weighted inputs with multiple variables. To address these challenges and assist network operators when formulating their network policies and performing network administrations, this thesis proposed novel approaches that are based on Data Envelopment Analysis (DEA) methodology to appropriately evaluate the efficiency of multicast energy and further minimizes energy transmission in ad hoc wireless networks without affecting the overall network performance. The DEA, which was used to study the relative efficiency and productivity of systems in Economic and Operational Research disciplines, is a non-parametric method that relies on linear programming technique for optimization of discrete units of observation called the decision making units (DMUs).
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    Performance analysis of optical burst switching network
    (2015) Lee, SeoungYoung; Murgu, Alexandru
    In this dissertation, after reviewing the new paradigm in the optical switching network invoked by the DWDM technology and studying the changes of the schemes, we design the new optical burst switching networks, analyze the performance of the proposed scheme and interpret the analysis results. For design point of view, the fairness guaranteeing scheme and burst blocking reduction schemes in the mesh networks, loss less burst transmission scheme in DWDM metro ring networks are considered. As a future broad band optical alternative, optical burst switching has been receive much focus. We review the property of the optical switching technologies such as optical packet switching, optical circuit switching, and optical burst switching. The benefits of the optical burst switching is illustrated. Even though optical burst switching has several advantage, it has intrinsic technology barrier. We study the research activities to remove the basic problem of optical burst switching. Optical deflection, optical burst segmentation, burst cloning, and burst piggy backing scheme is considered. To improve the network performance, we design optical burst switching network in mesh networks and metro ring networks. We also implement the proposed network by our own developed network test bench. We verify the proposed network performance by analyzing the network mathematically in terms of blocking rate, delay and throughput. The theoretical results are compared with the simulation results. The verification shows that our proposed schemes outperform those of the conventional scheme. Our mathematical models are also matched to the simulation results. The interpretation of the verification shows that our assumption and theoretical analysis is well designed. The results illustrate that the difference between the simulation results and mathematical results is within the considerable margin. The contribution of the thesis is that the performance improvement schemes in both of the mesh network and ring network are proposed and analyzed. By considering feasibility of the future optical networks, proposed scheme in this thesis is more deployable in commercial network in terms of the burst blocking rate and delay as well as the network stability.
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    Real-time bandwidth encapsulation for IP/MPLS Protection Switching
    (2011) Lubasi, Mampi Nakutoma; Murgu, Alexandru
    Bandwidth reservation and bandwidth allocation are needed to guarantee the protection of voice traffic during network failure. Since voice calls have a time constraint of 50 ms within which the traffic must be recovered, a real-time bandwidth management scheme is required. Such bandwidth allocation scheme that prioritizes voice traffic will ensure that the voice traffic is guaranteed the necessary bandwidth during the network failure. Additionally, a mechanism is also required to provide the bandwidth to voice traffic when the reserved bandwidth is insufficient to accommodate voice traffic. This mechanism must be able to utilise the working bandwidth or bandwidth reserved for lower priority applications and allocate it to the voice traffic when a network failure occurs.
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    Scalable Bandwidth Management in Software-Defined Networks
    (2021) Biyase, Lindokuhle Zakithi; Murgu, Alexandru
    There has been a growing demand to manage bandwidth as the network traffic increases. Network applications such as real time video streaming, voice over IP and video conferencing in IP networks has risen rapidly over the recently and is projected to continue in the future. These applications consume a lot of bandwidth resulting in increasing pressure on the networks. In dealing with such challenges, modern networks must be designed to be application sensitive and be able to offer Quality of Service (QoS) based on application requirements. Network paradigms such as Software Defined Networking (SDN) allows for direct network programmability to change the network behavior to suit the application needs in order to provide solutions to the challenge. In this dissertation, the objective is to research if SDN can provide scalable QoS requirements to a set of dynamic traffic flows. Methods are implemented to attain scalable bandwidth management to provide high QoS with SDN. Differentiated Services Code Point (DSCP) values and DSCP remarking with Meters are used to implement high QoS requirements such that bandwidth guarantee is provided to a selected set of traffic flows. The theoretical methodology is implemented for achieving QoS, experiments are conducted to validate and illustrate that QoS can be implemented in SDN, but it is unable to implement High QoS due to the lack of implementation for Meters with DSCP remarking. The research work presented in this dissertation aims at the identification and addressing the critical aspects related to the SDN based QoS provisioning using flow aggregation techniques. Several tests and demonstrations will be conducted by utilizing virtualization methods. The tests are aimed at supporting the proposed ideas and aims at creating an improved understanding of the practical SDN use cases and the challenges that emerge in virtualized environments. DiffServ Assured Forwarding is chosen as a QoS architecture for implementation. The bandwidth management scalability in SDN is proved based on throughput analysis by considering two conditions i.e 1) Per-flow QoS operation and 2) QoS by using DiffServ operation in the SDN environment with Ryu controller. The result shows that better performance QoS and bandwidth management is achieved using the QoS by DiffServ operation in SDN rather than the per-flow QoS operation.
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    A service composition platform in cloud computing using mobile devices for smart shopping
    (2016) Tsongoro, Lavender; Murgu, Alexandru
    The development of the Next Generation Networks (NGN) such as LTE, WiMax and 5G networks has resulted in the development of more diverse mobile services. Many voice and video services have been developed (e.g. Viber, Skype and WhatsApp). Social networking sites have also been developed (e.g. Facebook, Instagram and Twitter). Users of these services are increasingly expecting and demanding more complex services which have more capabilities that can improve their day to day business. Users want services that are reliable, fast and easy to use. To effectively design and implement services, Service Oriented Architecture (SOA) principles are useful and some of the advantages of designing services using SOA principles are: • Improved interoperability; • Cross platform and cross application integration; • Reusability; • Service composition. Service composition has the advantage that customized services with more features can be developed by combining two or more basic services. In this research, SOA principles are used to design a cloud based Mobile Smart Shopping Service Platform. Canal Walk Shopping Mall, which is located in Cape Town, South Africa is used as a case study. Various mobile services are composed in order to solve the problem of getting information about the services provided by the shopping mall and also to show the available parking bays, which has become a major concern due to the rapid growth of the surrounding residential and business areas. Performance measurements for the Smart Shopping service are then conducted to test its power consumption, memory usage, bandwidth usage and application timeline. Conclusions are drawn and recommendations for possible future development are then provided.
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    Topology-aware multicasting in phased mobile ad hoc networks for e-learning
    (2012) Chalemba, Leonard Edmond Khaiko; Murgu, Alexandru
    This thesis presents an adaptive multicast routing protocol called a Topology-Aware Polymorphic Multicast Routing Protocol (TAPMRP) for use in Mobile Ad hoc NETworks (MANETs). TAPMRP is proposed to serve E-Learning classroom (ELC) environments, which are generally characterised by minimal topology changes and distinct topologies. The research is motivated by the need to support students' learning efforts with MANET multicast services such as video streaming, offline websites and file sharing in a reliable and efficient manner.
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    Virtualization of multicast services in WiMAX networks
    (2017) Mukanyiligira, Didacienne; Murgu, Alexandru
    Multicast service is one of the methods used to efficiently manage bandwidth when sending multimedia content. To improve bandwidth utilisation, virtualization is often invoked because of its additional features such as bandwidth sharing and support of services that require high volumes of transactional data. Currently, network providers are concerned with the bandwidth amount for efficient use of the limited wireless network capabilities and the provision of a better quality of service. The virtualization design of a multicast service framework should satisfy several objectives. For example, it should enable the interchange of service delivery between multiple networks with one shareable network infrastructure. Also, it should ensure efficient use of network resources and guarantee users' demands of Quality of Service (QoS). Thus, the design of virtualization of multicast service framework is a complex research study. Due to the bandwidth-related arguments, a strong focus has been put on technical issues that facilitate virtualization in wireless networks. A well-designed virtualized network guarantees users with the required quality service. Similarly, virtualization of multicast service is invoked to improve efficient utilisation of bandwidth in wireless networks. As wireless links prove to be unstable, packet loss is unavoidable when multicast service-oriented virtual artefacts are incorporated in wireless networks. In this thesis, a virtualized multicast framework was modelled by using Generalized Assignment Problem (GAP) methodology. Mixed Integer Linear Programing (MILP) was implemented in MATLAB to solve the GAP model. This was to optimise the allocation of multicast traffic to the appropriate virtual networks. Thus, the developed model allows users to have interchangeable services offered by multiple networks. Furthermore, Network Simulator version 3 (NS-3) was used to evaluate the performance of the virtualized multicast framework. Three applications, namely, voice over IP (VoIP), video streaming, and file download have been used to evaluate the performance of a multicast service virtualization framework in Worldwide Interoperability for Microwave Access (WiMAX) networks using NS-3. The performance evaluation was based on whether MILP is used or not used. The results of experimentation have revealed that there is good performance of virtual networks when multicast traffic is sent over one single virtual network instead of sending it over multiple virtual networks. Similarly, the results show that the bandwidth is efficiently used because the multicast traffic is not delivered through multiple virtual networks. Overall, the concepts, the investigations and the model presented in this thesis can enable mobile network providers to achieve efficient use of bandwidth and provide the necessary means to support services for QoS differentiations and guarantees. Also, the multicast service virtualization framework provides an excellent tool that can enable network providers to interchange services. The developed model can serve as a basis for further extension. Specifically, the extension of the model can boost load balancing in the flow allocation problem and activate a virtual network to deliver traffic. This may rely on the QoS policy between network providers. Therefore, the model should consider the number of users in order to guarantee improved QoS.
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    WiMAX spectrum virtualization and network federation
    (2017) Ogunleye, Babatunde Samuel; Murgu, Alexandru
    Spectrum management in wireless broadband networks as regards its cost and its efficient usage has posed a huge challenge for mobile network operators. Traditionally, network operators had exclusive rights to access the band of spectrum allocated to them, but with the high price of spectrum license, it is becoming necessary to find alternative ways to use and access spectrum more efficiently. Resource virtualization is a method which has been extensively adopted in hardware computing for creating abstract versions of physical hardware resources and it has proven to be a powerful technique for customized resource provision and sharing. This idea of resource virtualization is gradually being transferred into the domain of wireless mobile network resource management but the ideas around it are still evolving. Since spectrum is an important wireless network resource, it is imperative to provide an efficient and cost effective means for the resource to be accessed and utilized. Therefore the idea of spectrum virtualization is investigated in this research as a possible solution to this problem. To expand on the notion of spectrum virtualization, this research further explores the idea of network federation. Network Federation involves the interconnection of diverse network components to be operated as a single seamless network. This will enable them share their network resources while the networks are geographically dispersed and managed by different network operators. To fully implement these concepts there is a need for a well-developed network framework. This research proposes two novel architectures for spectrum virtualization and network federation using the WiMAX (Worldwide Interoperability for Microwave Exchange) wireless broadband technology. The proposed WiMAX spectrum virtualization architecture introduces a novel entity known as the Virtual Spectrum Hypervisor (VS-Hypervisor). This VS-Hypervisor bears the responsibility of spectrum management and virtualization within the WiMAX framework. In the implementation of WiMAX network federation, the novel architecture enables the cooperative existence of multiple WiMAX base-stations having virtualization capabilities with overlapping cellular coverage areas for the purpose of sharing their spectrum resources. In this architecture, a novel federation control plane known as the Virtual Spectrum Exchange Locale (VSEL) is proposed. The VSEL facilitates the VS-Hypervisors in the federated physical base-stations to be able to negotiate and exchange spectrum between themselves to match their spectrum needs. The architectures for WiMAX spectrum virtualization and network federation was modelled and implemented using the OPNET Modeler. Results obtained validated their efficacy with respect to the effective management of the wireless network spectrum. Therefore this proposed network architectures would help network operators optimize their radio networks.