Dynamic Bandwidth Allocation

D. Energy Efficiency in Dynamic Bandwidth Allocation The concept of frequency reuse can be used for satellite non-adjacent cells but it will be limited due to formation of a large number of spot beams impractically. This is shown in figure 3, where the scenario of marked points in a cell is chosen in our model for allocating bandwidth dynamically. A switching office is employed for a satellite communication network system by a mobile satellite system having a satellite antenna for the transmission and reception of satellite messages via satellite to and from an earth station mobile. For transmission and reception of a satellite message, a central controller from the earth station mobile is used by connecting communication switching office to the satellite interface system. A network operations centre (NOC) of a mobile satellite system conducts the administrative functions associated with satellite management network system and also controls the resources of satellite management network system. NCC is the supporting system for communications circuits between satellite switching office and mobile communication system. The available circuits in circuit pools are managed by Central Group Controller (CGC) in NCC. CGC include components that are responsible for management of resources during clear down and call setup, management of database, traffic statistics, and management of call record and performance verification testing periodically.[15]

In this paper, we established a dynamic bandwidth allocation model based on the thinking of Agent, we established five sub-Agent: the business Agent, SLA Agent, application Agent, User Agent, user rating Agent, and decomposed the affecting factors about the bandwidth allocation among the OLT and ONU layer by layer. It may enhance the ability to describe the multiple factors in the process of bandwidth allocation. For the algorithm, we improved the algorithm of IPACT based on this model, introduced the idea of gaming and put forward a local redistribution algorithm based on bargain-bargain, regard the user level, delay, packet size as a bargaining conditions to sort the online users, it can enhance the efficiency of elimination about USR. According to the result of the simulation, the efficient of elimination about USR is significantly better than the traditional mechanism.

Communication networks create lot of interest due to their ready applicability in performance evaluation of several communication systems. In communication systems it is customary to consider that the arrivals are characterized by Poisson process. This assumption holds good if the arrivals are homogeneous and independent of time. But in many tele and satellite communication systems the arrivals are non homogeneous and the arrival rate is time dependent. Hence, in this paper we develop and analyze a three node communication network model with the assumption that the arrivals are characterized by non homogeneous Poisson process. It is further assumed that transmission time required by each packet at each node is dependent on the content of the buffer connected to it. The transient behavior of the network model is analyzed by deriving the system performance measures like mean number of packets in each buffer, mean delay in transmission, the throughput of the nodes, utilization of transmitters, etc,. The sensitivity analysis of the model reveals that the non homogeneous Poisson arrivals and dynamic bandwidth allocation strategy can reduce burstness in buffer and improve quality of service. A comparative study of communication network with non homogeneous Poisson arrivals and Poisson arrivals is also given.

According to the above analysis, it is observed that the dynamic bandwidth allocation strategy has a significant influence on all performance measures of the network. We also observed that the performance measures are highly sensitive towards smaller values of time. Hence, it is optimal to consider dynamic bandwidth allocation and evaluate the performance under transient conditions. It is also to be observed that the congestion in buffers and delays in transmission can be reduced to a minimum level by adopting dynamic bandwidth allocation. Table 2: Values of mean number of packets and mean delay of the network model with DBA and Homogeneous arrivals

When a renegotiation request is issued for any video trans- mission session, it will be checked immediately by realloca- tion control to verify if there is sufficient resource to meet the request. If the renegotiated resource can be accommodated, the renegotiation request is accepted, and otherwise is re- jected. Currently, whenever a renegotiation request fails due to lack of resource, a dynamic bandwidth allocation scheme is simply to reissue the renegotiation request consecutively at the next frame time (e.g., RED-VBR). Given a frame rate f (frame/sec.), any two consecutive renegotiation requests are only at one frame time 1 / f apart. Although this approach tries to explore the statistical multiplexing gain (SMG) at fine resolution level, it could unnecessarily introduce a lot of renegotiation and control overhead due to potential consec- utive renegotiation failures when the system lacks resource. In view of this, we introduce a new concept and method, re- ferred to as renegotiation control, into dynamic bandwidth allocation architecture (as illustrated in Figure 1). The idea of the proposed renegotiation control is to avoid consecutive renegotiation requests after the previous renegotiation fail- ure, by exponentially slowing down the process of reissuing renegotiations when the system is undergoing resource in- sufficiency. In this regard, the current aggressive (frame-by- frame) practice of re-renegotiations can be viewed as a de- fault renegotiation control method. Inspired by the success of binary exponential backo ff (BEB) algorithm in Ethernet and IEEE 802 . 11 distributed coordination function (DCF) for wireless local area networks, we believe that BEB can also naturally fit in the renegotiation control situation identified above. Thus, a BEB-based renegotiation control algorithm is proposed as in Algorithm 1, and is evaluated through simu- lations in Section 5.

From the above analysis it is observed that the dynamic bandwidth allocation strategy has an important influence on all performance measures of the network. It is also observed that these performance measures are also sensitive towards the probability parameters , 𝜏, 𝜑, , which causes feedback of packets to the first, second and third transmitters.

High utilization is one of the design goals for MPCP-based dynamic bandwidth allocation (DBA) algorithms in GiGabite passive optical networks (EPON). However, utilization is sacrificed in order to meet the delay limits of the applications in most DBA design schemes. This paper proposes a dynamic bandwidth allocation algorithm based on sorting report messages with additive-polling thresholds (AP-Sort DBA). This has the characteristics of high utilization and low delay during medium network loading. AP-Sort DBA is an extension of the adaptive dynamic bandwidth allocation algorithm with sorting report messages (Sort-DBA) and promotes utilization by reduction of unused slot remainders (USR) and distribution of excess bandwidth. For performance evaluation in terms of average delay, average queue size, loss rate and utilization, five DBA schemes are simulated, namely AP-Sort DBA, interleaved polling with adaptive cycle time (IPACT), dynamic bandwidth allocationOur focus is how the wireless upstream traffic based on CluLoR going into the optical access network performs when conventional wired traffic is included in the optical network. We evaluate the delay performance for different practical scenarios and examine the underloading and overloading of the wireless and wired traffic respectively on FiWi networks. Our evaluations indicate that the performance impact of DBA algorithms depends on the source of the traffic and we provide comparisons in this project.

We propose request-based dynamic bandwidth allocation (DBA) of gigabit passive optical network (GPON). The opti- cal line terminal (OLT) in GPON grants bandwidth to optical network units (ONUs). ONUs report request bandwidth which depends on queue lengths of traffic containers (TCONTs) to the OLT. In the OLT, DBA of GPON supports a request-based polling order to allocate bandwidth. Our request-based dynamic bandwidth allocation focuses on weight assignments in the request-based polling order. Weight assignments allocate bandwidth in proportion to guaranteed and request bandwidth. We use the C program to simulate results. Simulated results indicate improved performance in queueing delay when total offered loads are or are not shared uniformly to TCONTs.

Regarding the importance of dynamic bandwidth allocation in next generation access networks based on EPON technology, in this paper we have proposed Parnian, an optimal DBA method based on auction theory. In this new method, the dynamic bandwidth allocation is performed by running auction in two stages, one for the ONUs under the OLT management and another one for the users under the ONU’s control. Simulation results show that Parnian, in comparison with FSD-SLA and "limited service" IPACT experiences more delay, but regarding other quality of service parameters such as packet loss ratio, line utilization, and throughput, it has better performance. On the other hand, the average execution time in Parnian method is better than the "limited service" IPACT and FSD-SLA approaches and, as a result, it works faster. The future research potential in the dynamic bandwidth allocation process in EPON networks will allow us to go further and open new research horizons by utilizing heuristics methods such as genetics algorithm, cellular automata, neural networks, and etc. instead of running auction in user level. Moreover, it would be possible to apply this new DBA method in Wi-Fi and WiMax environments and evaluate the performance.

In this paper, we simulate a network with a combination of wired and wireless traffic in FiWi Network, introduce a DBA space and qualitatively analyze it, which to the best of our knowledge, have not been extensively analyzed before in literature. An interesting practical application is the Cloud mobile host implementation, where we have multiple mobile hosts accessing data from Cloud servers. Cloud server are examples of heavily loaded wired networks, and mobile hosts are wireless nodes connected to the gateway at their average data rate. We also analyze the delay performance of different DBAs and propose the usefulness of each DBA for specific scenarios that are of practical importancewe introduce dynamic bandwidth allocation (DBAs) for the fiber network and the importance of it when used with wireless network. We introduce a DBA space for the FiWi networks which combines different combination of grant transmission of the fiber network with that of the wireless network. The wired network follows the MPCP protocol (Multi-Point Control Protocol) in a time-sharing basis in the upstream direction and broadcast protocol in the downstream direction as used in IEEE 802.3ah.

The rest of the paper is organized as follows. In Section 2, related works are reviewed. Sec- tion 3 describes the dynamic bandwidth alloca- tion based on scene changes for pre-recorded videos. A simple procedure for scene change identification is adopted, and ideas for improv- ing the bandwidth utilization are also intro- duced. Section 4 covers the on-line dynamic bandwidth allocation for real time video deli- very. Algorithms to reduce renegotiation fre- quency and improve bandwidth utilization are also presented. Conclusions are drawn in Sec- tion 5, and simulation results are presented in respective sections.

The preceding results have for the most part considered an injection rate of 1.0 for the sake of pushing each allocation scheme to its limits. However, real-world applications often have far lower injection rates. One such example is the Map-Reduce benchmark [44] suite for multiprocessor computing. Various benchmarks are chosen from this suite for evaluation on various allocation schemes because of their variation in average injection rate. The simulation is based on traces from execution of the benchmarks on the gem5 [45] simulator. Figure 17 shows the average effective bandwidth per Node. The effective bandwidth is a combination of the latency determined by the bandwidth available to a node and the delay in allocating the bandwidth due to starvation. These benchmarks are evaluated on various allocation schemes. The injection rates are normalized to that of the most-frequently injecting node. Due to the low average injection rates (shown in Figure 18), a lower system-wide average resource amount μ s can be

In tree-based networks, nodes closer to the root need to forward more data packets than others. Traditional MAC protocols tend to provide fair access and hence are not suitable in such network architecture. If tradi- tional MAC protocols are used in many-to-one network topology, congestion towards the root node is inevitable. Recognizing this fact in WSN, a number of protocols such as presented in [7,8,11,15-18] are developed. A hybrid approach using schedule-based medium access in traffic- intensive regions and contention-based MAC in low traf- fic zones is proposed in [8,15,17]. Z-MAC [8] acts like a contention-based protocol under low traffic conditions and a schedule-based protocol under high traffic condi- tions by using the schedule computed by DRAND (Dis- tributed RAND) [19]. It allocates time slots to every node ensuring that no two nodes among a 2-hop neighborhood are assigned the same time slot. In order to improve uti- lization in low load situation, Z-MAC allows ‘non-owners’ of a slot to contend for a slot if it is not being used by its ‘owner.’ Similarly, Funneling-MAC [15] tried to miti- gate the funneling problem by a sink-oriented scheduling protocol which is also a hybrid of TDMA and CSMA pro- tocols. It uses TDMA scheduling in the intensity region and employs CSMA in the rest of the network to pro- vide flexibility. It is localized in operation because TDMA only operates in the intensity region close to the sink and not across the complete sensor network. These two pro- tocols employ fixed slot TDMA and hence do not provide any priority to the nodes considering their requirements. I-MAC [16] assigns different levels of priority to differ- ent nodes according to their role in the network. During scheduling of any slot, the owner of the slot gets the first priority. The non-owner nodes can compete to use a slot only when the owner node does not need it. The chance of getting a slot by a non-owner node also depends on its priority level. Queue-MAC [10] is another hybrid proto- col which has addressed the issue of burst network traffic by allocating time slots of dynamic size. In this protocol, packets coming from the children nodes carry their load information through a special field called queue indicator. The frame comprises a CSMA and a TDMA compo- nent. Initially, a node starts its transmission using CSMA protocol. With an increase in load, the active TDMA period is accordingly extended by adding more time slots to increase the bandwidth. Queue-MAC considers only single-hop topology because of which it needs multi-hop extension to fit in WiLD networks.

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Efficient dynamic resource provisioning mechanisms are necessary to the development and automation of Quality of Service networks. In telecommunication networks, resource allocation is performed mainly in a static way, on time scales on the order of hours to months. However, statically provisioned network resource can become insufficient or considerably under-utilized if traffic statistics change significantly. Therefore, a key challenge for the deployment of Quality of Service networks is the development of solutions that can dynamically track traffic statistics and allocate network resources efficiently, satisfying the QoS requirements of users while aiming at maximizing, at the same time, resource utilization and network revenue. Recently, dynamic bandwidth allocation has attracted research interest [4].

Developing a resource allocation protocol for the converged network complies with both the Multipoint Control Protocol (MPCP)-based PON Dynamic Bandwidth Allocation (DBA) and an effective mapping mechanism between GPON priority queues and LTE service connections to support high bandwidth and QoS-intensive applications is one of key challenges. It aims at smoothing the stock of resources which reducing both excess inventories and shortages, and meets different user's requirements using the corresponding different priorities to guarantee QoS. However, the asynchrony problem in upstream bandwidth allocation will occur due to the cycle time of GPON (usually is between 1ms and 2ms) and the frame size of LTE (usually is 5ms or 10ms) are mismatched. This paper builds on the QoS mapping strategy and proposes a Synchronous Interleaved Dynamic Bandwidth Assignment (SIDBA) scheme based on the Interleaved Dynamic Bandwidth Allocation in [4] to alleviate the asynchrony problem in the proposed GPON-LTE Converged Network Architecture (GLCNA).

simultaneously, efficient utilization of the network resource. Network bandwidth design, simulation, and management tools therefore represent a viable alternative for network planners to rapidly determine correct configurations based on actual mission requirements and current systems availability. The results yield effective utilization of the available bandwidth and contribute to determining the prioritization of the data rate. Where traffic statistics change significantly, a deployment of solutions that can dynamically track traffic statistics for efficient allocation of network resources and satisfy the QoS requirements of users while maximizing (at the same time) resource utilization and network revenue are necessary. Dynamic bandwidth allocation has attracted numerous research interests and many algorithms have been proposed in the literature (see, Campbell and Liao, 2004; Schulzrinne and Wang, 2005; Ahmed, Boutaba and Mehaoua, 2005; Mahajan Parashar and Ramanathan, 2004; Kelly, 1997). Many tools and techniques have also been developed to predict the performance of cellular networks. Broadly speaking, all these tools fall under one of the following approaches: discrete event simulation and mathematical modeling (Wombell, 1999). In the first approach, bandwidth utilization and network performance are estimated by modeling every individual packets traversing the network. On the other hand, the main idea of mathematical modeling lies in building an abstract framework of the network consisting of a number of equations founded on sound theoretical concepts. This model is then used to compute traffic patterns, infer bandwidth utilization trends and compute the expected network performance. The Network Simulator (NS) (McCanne and Floyd, 2007), and the Georgia Tech Network Simulator (Riley, 2003), are network simulation tools based on the descrete event approach. Network bandwidth utilization is estimated using a simulation engine that tracks packet transmissions from origin to destination (Breslau, Estrin, Fall, Floyd, Heidemann, Helmy, Huang, McCanne, Varadhan, Xu and Yu, 2000). Some tools have incorporated additional features to increase the accuracy of estimations, such as queing behaviour and parallel processing. The Mathematical modeling approach includes a significant number of tools such as CACI Network Simulation Suite and NetraMet (Brownlee, 1997). These tools collect statistical information from the network in order to produce an overall picture of the traffic and link utilization patterns. This can be achieved by either actively probing the network to collect data or by other passive means that rely on different networking protocol characteristics to deduce the required information.

Additional bandwidth allocation algorithms for EPON-WiMAX networks have been proposed [18], [19], and [20]. QoS-based Dynamic Bandwidth Allocation (QDBA) [19] is incorporated with the Prediction-based Fair Excessive Bandwidth Allocation (PFEBA) scheme in EPON to enhance the system performance. In QDBA, each ONU is in charge of three queues with different priorities. It also classifies WiMAX traffics into three priority levels and maps them to the queues of ONU. In addition to QDBA, the authors in [19] proposed a queue-based scheduling scheme that effi- ciently satisfies the demand for bandwidth requests and enhances the efficiency of the system. The DBA scheme [18] considers the features of the converged network proposed in the same paper to enable a smooth data transmission across optical and wireless networks, and an end-to-end differentiated service to user traffic of diverse QoS requirements. This QoS-aware DBA scheme supports bandwidth fairness at the ONU-BS level and class-of-service fairness at the WiMAX subscriber station level.

In Wireless Sensor Networks (WSN) a set of motes moni- tors the environment by measuring some physical phenom- ena such as humidity, light, temperature, vibrations. The coexistence of different data types arises the problem of as- signing the network resources in a fair way by taking into ac- count possible different priorities among the traffic streams. In this paper we propose an allocation control scheme which is easy to implement, meets the limited resources of sensor nodes, and does not require extra control traffic in the WSN. Our scheme is based on the idea that the motes maintain a window with the classes of the latest transmissions. We pro- pose an analytical model and provide an algorithm to study the performance of this allocation scheme with respect to the throughput and the fairness achieved. The model is a continuous time Markov chain which is proved to be dy- namically reversible (although not reversible) and admits a product-form equilibrium distribution.

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