Ethernet - a survey on its fields of application

During the last decades, Ethernet progressively became the most widely used local area networking (LAN) technology. Apart from LAN installations, Ethernet became also attractive for many other fields of application, ranging from industry to avionics, telecommunication, and multimedia. The expanded application of this technology is mainly due to its significant assets like reduced cost, backward-compatibility, flexibility, and expandability. However, this new trend raises some problems concerning the services of the protocol and the requirements for each application. Therefore, specific adaptations prove essential to integrate this communication technology in each field of application. Our primary objective is to show how Ethernet has been enhanced to comply with the specific requirements of several application fields, particularly in transport, embedded and multimedia contexts. The paper first describes the common Ethernet LAN technology and highlights its main features. It reviews the most important specific Ethernet versions with respect to each application field’s requirements. Finally, we compare these different fields of application and we particularly focus on the fundamental concepts and the quality of service capabilities of each proposal

Performance evaluation of an open distributed platform for realistic traffic generation

Network researchers have dedicated a notable part of their efforts to the area of modeling traffic and to the implementation of efficient traffic generators. We feel that there is a strong demand for traffic generators capable to reproduce realistic traffic patterns according to theoretical models and at the same time with high performance. This work presents an open distributed platform for traffic generation that we called distributed internet traffic generator (D-ITG), capable of producing traffic (network, transport and application layer) at packet level and of accurately replicating appropriate stochastic processes for both inter departure time (IDT) and packet size (PS) random variables. We implemented two different versions of our distributed generator. In the first one, a log server is in charge of recording the information transmitted by senders and receivers and these communications are based either on TCP or UDP. In the other one, senders and receivers make use of the MPI library. In this work a complete performance comparison among the centralized version and the two distributed versions of D-ITG is presented

When Should I Use Network Emulation?

The design and development of a complex system requires an adequate methodology and efficient instrumental support in order to early detect and correct anomalies in the functional and non-functional properties of the tested protocols. Among the various tools used to provide experimental support for such developments, network emulation relies on real-time production of impairments on real traffic according to a communication model, either realistically or not. This paper aims at simply presenting to newcomers in network emulation (students, engineers, ...) basic principles and practices illustrated with a few commonly used tools. The motivation behind is to fill a gap in terms of introductory and pragmatic papers in this domain. The study particularly considers centralized approaches, allowing cheap and easy implementation in the context of research labs or industrial developments. In addition, an architectural model for emulation systems is proposed, defining three complementary levels, namely hardware, impairment and model levels. With the help of this architectural framework, various existing tools are situated and described. Various approaches for modeling the emulation actions are studied, such as impairment-based scenarios and virtual architectures, real-time discrete simulation and trace-based systems. Those modeling approaches are described and compared in terms of services and we study their ability to respond to various designer needs to assess when emulation is needed

ANALYSIS OF DATA & COMPUTER NETWORKS IN STUDENTS' RESIDENTIAL AREA IN UNIVERSITI TEKNOLOGI PETRONAS

In Universiti Teknologi Petronas (UTP), most of the students depend on the Internet and computer network connection to gain academics information and share educational resources. Even though the Internet connections and computers networks are provided, the service always experience interruption, such as slow Internet access, viruses and worms distribution, and network abuse by irresponsible students. Since UTP organization keeps on expanding, the need for a better service in UTP increases. Several approaches were put into practice to address the problems. Research on data and computer network was performed to understand the network technology applied in UTP. A questionnaire forms were distributed among the students to obtain feedback and statistical data about UTP's network in Students' Residential Area. The studies concentrate only on Students' Residential Area as it is where most of the users reside. From the survey, it can be observed that 99% of the students access the network almost 24 hours a day. In 2005, the 2 Mbps allocated bandwidth was utilized 100% almost continuously but in 2006, the bottleneck of Internet access has reduced significantly since the bandwidth allocated have been increased to 8 Mbps. Server degradation due to irresponsible acts by users also adds burden to the main server. In general, if the proposal to ITMS (Information Technology & Media Services) Department for them to improve their Quality of Service (QoS) and established UTP Computer Emergency Response Team (UCert), most of the issues addressed in this report can be solved

Real-time detection of grid bulk transfer traffic

The current practice of physical science research has yielded a continuously growing demand for interconnection network bandwidth to support the sharing of large datasets. Academic research networks and internet service providers have provisioned their networks to handle this type of load, which generates prolonged, high-volume traffic between nodes on the network. Maintenance of QoS for all network users demands that the onset of these (Grid bulk) transfers be detected to enable them to be reengineered through resources specifically provisioned to handle this type of traffic. This paper describes a real-time detector that operates at full-line-rate on Gb/s links, operates at high connection rates, and can track the use of ephemeral or non-standard ports

Converged IP-over-standard ethernet progress control networks for hydrocarbon process automation applications controllers

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.The maturity level of Internet Protocol (IP) and the emergence of standard Ethernet interfaces of Hydrocarbon Process Automation Application (HPAA) present a real opportunity to combine independent industrial applications onto an integrated IP based network platform. Quality of Service (QoS) for IP over Ethernet has the strength to regulate traffic mix and support timely delivery. The combinations of these technologies lend themselves to provide a platform to support HPAA applications across Local Area Network (LAN) and Wide Area Network (WAN) networks. HPAA systems are composed of sensors, actuators, and logic solvers networked together to form independent control system network platforms. They support hydrocarbon plants operating under critical conditions that — if not controlled — could become dangerous to people, assets and the environment. This demands high speed networking which is triggered by the need to capture data with higher frequency rate at a finer granularity. Nevertheless, existing HPAA network infrastructure is based on unique autonomous systems, which has resulted in multiple, parallel and separate networks with limited interconnectivity supporting different functions. This created increased complexity in integrating various applications and resulted higher costs in the technology life cycle total ownership. To date, the concept of consolidating HPAA into a converged IP network over standard Ethernet has not yet been explored. This research aims to explore and develop the HPAA Process Control Systems (PCS) in a Converged Internet Protocol (CIP) using experimental and simulated networks case studies. Results from experimental and simulation work showed encouraging outcomes and provided a good argument for supporting the co-existence of HPAA and non-HPAA applications taking into consideration timeliness and reliability requirements. This was achieved by invoking priority based scheduling with the highest priority being awarded to PCS among other supported services such as voice, multimedia streams and other applications. HPAA can benefit from utilizing CIP over Ethernet by reducing the number of interdependent HPAA PCS networks to a single uniform and standard network. In addition, this integrated infrastructure offers a platform for additional support services such as multimedia streaming, voice, and data. This network‐based model manifests itself to be integrated with remote control system platform capabilities at the end user's desktop independent of space and time resulting in the concept of plant virtualization

Mathematical modelling of end-to-end packet delay in multi-hop wireless networks and their applications to qos provisioning

This thesis addresses the mathematical modelling of end-to-end packet delay for Quality of Service (QoS) provisioning in multi-hop wireless networks. The multi-hop wireless technology increases capacity and coverage in a cost-effective way and it has been standardised in the Fourth-Generation (4G) standards. The effective capacity model approximates end-to-end delay performances, including Complementary Cumulative Density Function (CCDF) of delay, average delay and jitter. This model is first tested using Internet traffic trace from a real gigabit Ethernet gateway. The effective capacity model is developed based on single-hop and continuous-time communication systems but a multi-hop wireless system is better described to be multi-hop and time-slotted. The thesis extends the effective capacity model by taking multi-hop and time-slotted concepts into account, resulting in two new mathematical models: the multi-hop effective capacity model for multi-hop networks and the mixed continuous/discrete-time effective capacity model for time-slotted networks. Two scenarios are considered to validate these two effective capacity-based models based on ideal wireless communications (the physical-layer instantaneous transmission rate is the Shannon channel capacity): 1) packets traverse multiple wireless network devices and 2) packets are transmitted to or received from a wireless network device every Transmission Time Interval (TTI). The results from these two scenarios consistently show that the new mathematical models developed in the thesis characterise end-to-end delay performances accurately. Accurate and efficient estimators for end-to-end packet delay play a key role in QoS provisioning in modern communication systems. The estimators from the new effective capacity-based models are directly tested in two systems, faithfully created using realistic simulation techniques: 1) the IEEE 802.16-2004 networks and 2) wireless tele-ultrasonography medical systems. The results show that the estimation and simulation results are in good agreement in terms of end-to-end delay performances

Dynamic bandwidth management with service differentiation over ethernet passive optical networks

Ethernet passive optical networks (EPONs) address the first mile of the communication infrastructure between the service provider central offices and the customer sites. As a low-cost, high speed technology, EPONs are deemed as the solution to the bottleneck problem of the broadband access network. A major feature of EPONs is the utility of a shared upstream channel among the end users. Only a single optical network unit (GNU) may transmit during a timeslot to avoid data collisions. In order to provide diverse quality of service (QoS), the bandwidth management of the upstream channel is essential for the successful implementation of EPONs, and thus, an efficient medium access control is required to facilitate statistical multiplexing among local traffics. This dissertation addresses the upstream bandwidth allocation over EPONs. An efficient mechanism, i.e., limited sharing with traffic prediction (LSTP), has been proposed to arbitrate the upstream bandwidth among ONUs. The MultiPoint Control Protocol (MPCP) messages, which are stipulated by the IEEE 802.3ah Ethernet in the First Mile (EFM) Task Force, are adopted by LSTP to facilitate the dynamic bandwidth negotiation between an GNU and the OLT. The bandwidth requirement of an ONU includes the already enqueued frames and the predicted incoming frames during the waiting time. The OLT arbitrates the bandwidth assignment based on the queue status report from an GNU, the traffic prediction, and the agreed service contract. With respect to the performance evaluation, theoretical analysis on the frame loss, the frame delay, and the queue length has been conducted. The quantitative results demonstrate that 1) the innovative LSTP mechanism dynamically allocates the upstream bandwidth among multiple ONUs; 2) the traffic predictor at the OLT delivers satisfactory prediction for the bursty self-similar traffic, and thereby, contributing to the reduction of frame loss, frame delay, and queue length; and 3) the bandwidth arbitration at the OLT effectively restricts the aggressive bandwidth competition among ONUs by adopting the service level agreement (SLA) parameter as the upper bound. Aside from analysis, the LSTP mechanism has been substantiated by experimental simulations. In order to differentiate the service provisioning among diverse users, LSTP is further enhanced with the support of dynamic bandwidth negotiation based on multiple queues. The incoming traffics are first classified into three classes, and then enqueued into the corresponding queues. A traffic predictor is dedicated to one class of traffic from an GNU. Service differentiation among classes are provided by the combination of queuing and scheduling at the GNU side. At the OLT side, the bandwidth allocation for each class of traffic is based on the reported queue status and the traffic prediction, and is upper-bounded by the SLA parameter. Experimental simulations have justified the feasibility of providing service differentiation over the broadband EPONs

On IP over WDM burst-switched long haul and metropolitan area networks

The IP over Wavelength Division Multiplexing (WDM) network is a natural evolution ushered in by the phenomenal advances in networking technologies and technical breakthroughs in optical communications, fueled by the increasing demand in the reduction of operation costs and the network management complexity. The unprecedented bandwidth provisioning capability and the multi-service supportability of the WDM technology, in synergy with the data-oriented internetworking mechanisms, facilitates a common shared infrastructure for the Next Generation Internet (NGJ). While NGI targets to perform packet processing directly on the optical transport layer, a smooth evolution is critical to success. Intense research has been conducted to design the new generation optical networks that retain the advantages of packet-oriented transport prototypes while rendering elastic network resource utilization and graded levels of service. This dissertation is focused on the control architecture, enabling technologies, and performance analysis of the WDM burst-switched long haul and Metropolitan Area Networks (MANs). Theoretical analysis and simulation results are reported to demonstrate the system performance and efficiency of proposed algorithms. A novel transmission mechanism, namely, the Forward Resource Reservation (ERR) mechanism, is proposed to reduce the end-to-end delay for an Optical Burst Switching (OBS)-based IP over WDM system. The ERR scheme adopts a Linear Predictive Filter and an aggressive reservation strategy for data burst length prediction and resource reservation, respectively, and is extended to facilitate Quality of Service (QoS) differentiation at network edges. The ERR scheme improves the real-time communication services for applications with time constraints without deleterious system costs. The aggressive strategy for channel holding time reservations is proposed. Specifically, two algorithms, the success probability-driven (SPD) and the bandwidth usage-driven (BUD) ones, are proposed for resource reservations in the FRRenabled scheme. These algorithms render explicit control on the latency reduction improvement and bandwidth usage efficiency, respectively, both of which are important figures of performance metrics. The optimization issue for the FRR-enabled system is studied based on two disciplines - addressing the static and dynamic models targeting different desired objectives (in terms of algorithm efficiency and system performance), and developing a \u27\u27crank back\u27\u27 based signaling mechanism to provide bandwidth usage efficiency. The proposed mechanisms enable the network nodes to make intelligent usage of the bandwidth resources. In addition, a new control architecture with enhanced address resolution protocol (E-ARP), burst-based transmission, and hop-based wavelength allocation is proposed for Ethernet-supported IP over WDM MANs. It is verified, via theoretical analysis and simulation results, that the E-ARP significantly reduces the call setup latency and the transmission requirements associated with the address probing procedures; the burst-based transport mechanism improves the network throughput and resource utilization; and the hop-based wavelength allocation algorithm provides bandwidth multiplexing with fairness and high scalability. The enhancement of the Ethernet services, in tandem with the innovative mechanisms in the WDM domain, facilitates a flexible and efficient integration, thus making the new generation optical MAN optimized for the scalable, survivable, and IP-dominated network at gigabit speed possible

Overview of UMTS network evolution through radio and transmission feature validation

This project is based on several UMTS network feature validation with the aim to provide an end-to-end in-depth knowledge overview gained in parallel in the areas of radio network mobility processes (cell camping and inter-system handover), Quality of Service improvement for HSPA data users and transport network evolution towards the All-IP era.Hardware and software validation is a key step in the relationship between the mobile network operator and the vendor. Through this verification process, while executing that functionality or testing a specific hardware, the difference between the actual result and expected result can be better understood and, in turn, this in-depth knowledge acquisition is translated into a tailored usage of the product in the operator’s live network. As a result, validation helps in building a better product as per the customer’s requirement and helps satisfying their needs, which positively impacts in the future evolution of the vendor product roadmap implementation process for a specific customer. This project is based on several Universal Mobile Telecommunication Services (UMTS) network feature validation with the aim to provide an end-to-end in-depth knowledge overview gained in parallel in the areas of radio network mobility processes (cell camping and inter-system handover), Quality of Service improvement for High Speed Downlink Packet Access (HSPA) data users and transport network evolution towards the All-IP era.Las campañas de validación hardware y software son un paso clave en las relaciones comerciales establecidas entre un operador de telecomunicaciones y su proveedor de equipos de red. Durante los procesos de certificación, mientras se ejecuta una funcionalidad software o se valida un determinado hardware, se obtiene un conocimiento profundo de la diferencia entre el resultado obtenido y el esperado, repercutiendo directamente en un uso a medida de dicha funcionalidad o hardware en la propia red del cliente. Como consecuencia de lo anterior, podemos aseverar que los procesos de validación permiten en gran medida al proveedor adaptarse mejor a los requerimientos del cliente, ayudando a satisfacer realmente sus necesidades. Esto implica directamente un impacto positivo en la futura evolución del portfolio que el fabricante ofrece a un determinado cliente. Este proyecto está basado en la validación de diferentes funcionalidades de red UMTS, cuyo objetivo es proporcionar un conocimiento global de distintos aspectos que conforman el funcionamiento de una red de telecomunicaciones 3G, como son los procesos de movilidad de acceso radio (acampado de red y handover inter-sistema), las mejoras en la calidad de servicio para usuarios de datos HSPA y la convergencia de la red de transporte hacia la era IP.Els processos de validació hardware i software són un punt clau en les relacions comercials establertes entre un operador de telecomunicaciones i el proveïdor d'equipament de la xarxa. En el transcurs dels processos de certificació, a la mateixa vegada que s'executa una funcionalitat software o es valida un determinat hardware, s'obtenen grans coneixements respecte la diferència entre el resultat obtingut i l'esperat, que són d'aplicació directa a l'hora d'establir un ús adpatat a la xarxa del client. En conseqüència, podem asseverar que les campanyes de validació permeten en gran mesura al proveïdor adaptar-se millor als requeriments del client, ajudant a satisfer realment les seves necessitats. Això implica directament un impacte positiu en la futura evol.lució del portfoli que el fabricant ofereix a un determinat client. Aquest projecte es basa en la presentació d'un procès de validació de diferents funcionalitats relacionades amb la xarxa UMTS, amb l'objectiu de proporcionar un coneixement global de la varietat d'aspectes que conformen el funcionament d'una xarxa de telecomunicacions 3G, com són els processos de mobilitat en accès radio (acampat de l'usuari i handover inter-sistema), millores en la qualitat de servei per a usuaris de dades HSPA i la convergència de la xarxa de transport cap a l'era IP