• IEIE Transactions on Smart Processing and Computing
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• v.1 no.1
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• pp.27-33
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• 2012

The Ethernet Passive Optical Network (EPON) has been considered to be one of the most promising solutions for the implementation of the Fiber To The Home (FTTH) technology designed to ameliorate the "last mile" bandwidth bottleneck. In the EPON network, an efficient and fair bandwidth allocation is a very important issue, since multiple optical network units (ONUs) share a common upstream channel for packet transmission. To increase bandwidth utilization, an EPON system must provide a way to adaptively allocate the upstream bandwidth among multiple ONUs in accordance to their bandwidth demands and requirements. We present a new hybrid method that satisfies these requirements. The advantage of our method comes from the consideration of application-specific bandwidth allocation and the minimization of the idle bandwidth. Our simulation results show that our proposed method outperforms existing dynamic bandwidth allocation methods in terms of bandwidth utilization.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.11
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• pp.943-954
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• 2000

Fieldbus is the lowest level industrial network in the communication hierarchy of factory automation and distributed process control systems. Data generated from field devices are largely divided into three categories : time-critical, periodic and time-available data. Because these data share one fieldbus medium, it needs a method that allocates these data to the bandwidth-limited fieldbus medium. This paper introduces an implementation method of bandwidth allocation scheme on PROFIBUS. In order to implement bandwidth allocation scheme on PROFIBUS, the following functions need to be supplemented on the FDL(Fieldbus Datalink Layer) protocol: (i) separation of medium bandwidth into periodic and non-periodic intervals, (ii) synchronization of node timers over a local link. In order to examine the validity of bandwidth allocation scheme on PROFIBUS, this paper develops an experimental model of a network system. The results obtained from the experimental model show that the bandwidth allocation scheme satisfies the performance requirement of time-critical, periodic and time-available data.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.10
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• pp.882-890
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• 2001

The data link layer of Foundation Fieldbus is operated on the basis of scheduling and token-passing disciplines. This paper presents a network design method of Foundation Fieldbus using a bandwidth allocation scheme. Fieldbus traffic consists of periodic data and sporadically generated time-critical and time-available data. The bandwidth allocation scheme schedules the transmission of periodic data. Time-critical and time-available data are transmitted via a token-passing service. The validity of this bandwidth allocation scheme is determined using an experimental model of a network system. The results obtained from the experimental model show that the proposed scheme restricts the delay of both periodic and time-critical data to a pre-specified bound. The proposed bandwidth allocation scheme also fully utilizes the bandwidth resource of the network system.

• Management Science and Financial Engineering
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• v.16 no.1
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• pp.59-79
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• 2010

This paper considers bandwidth allocation and scheduling problems on Ethernet Passive Optical Networks (EPON). EPON is one of the good candidates for the optical access network. This paper formulates the bandwidth allocation problem as a nonlinear mathematical one and characterizes the optimal bandwidth allocation which maximizes weighted sum of throughput and fairness. Based upon the characterization, two heuristic algorithms are suggested with various numerical tests. The test results show that our algorithms can be used for efficient bandwidth allocation on the EPON. This paper also shows that the WSPT (Weighted Shortest Processing Time) rule is optimal for minimization the total delay time in transmitting the traffic of the given allocated bandwidth.

• The KIPS Transactions:PartC
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• v.18C no.2
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• pp.97-102
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• 2011

Since the game theory provides a theoretical ground to distribute a shared resource between demanding users in a fair and efficient manner, it has been used for the bandwidth allocation problem in a network. However, the bandwidth allocation schemes with different game theory assign different amount of bandwidth in the same operational environments. However, only the mathematical framework is adopted when a bandwidth allocation scheme is devised without quantitatively comparing the results when they applied to the bandwidth allocation problem. Thus, in this paper, we compare the characteristics of the bandwidth allocation schemes using the bankrupt game theory and the bargaining game theory when they applied to the situation where nodes are competing for the bandwidth in a network. Based on the numerical results, we suggest the future research direction.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.52-55
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• 2004

Digital communication networks have become a core technology in advanced building automation systems. BACnet(${\underline{B}}uilding$ ${\underline{A}}utomation$ and ${\underline{C}}ontrol$ ${\underline{net}}works$) is a standard data communication protocol designed specifically for building automation and control systems. BACnet adopts Master-Slave/Token-Passing (MS/TP) protocol as one of its field level networks. In this study, we introduce a method of implementing bandwidth allocation scheme in the MS/TP protocol. The bandwidth allocation scheme improves the capability of real-time communication of the original MS/TP protocol. The bandwidth allocation scheme introduced in this paper can be easily implemented in the existing MS/TP protocol with a slight modification. In this study, we actually developed the hardware and firmware of MS/TP module in which bandwidth allocation scheme is implemented.

• Proceedings of the KIEE Conference
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• 2002.11c
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• pp.430-433
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• 2002

Fieldbus traffic consists of periodic, time-critical and time-available data. A bandwidth allocation scheme allocates periodic, time-critical and time-available data traffic to the bandwidth-limited network resource. This paper presents an implementation method of the bandwidth allocation scheme in the user layer of Foundation fieldbus. In this study, an experimental model of a Foundation Fieldbus network system is developed. Using the experimental model, validity of the bandwidth allocation scheme is examined. The results obtained from the experimental model show that the proposed scheme restricts the delay of both periodic and time-critical data to a pre-specified bound. The bandwidth allocation scheme also fully utilized the bandwidth resource of the network system.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.11
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• pp.1144-1155
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• 2006

Digital communication networks have become a core technology in advanced building automation systems. BACnet(Building Automation and Control networks) is a standard data communication protocol designed specifically for building automation and control systems. BACnet adopts Master-Slave/Token-Passing(MS/TP) protocol as one of its field level networks. In this study, we introduce a method of implementing a bandwidth allocation scheme in the MS/TP protocol. The bandwidth allocation scheme improves the capability of real-time communication of the original MS/TP protocol. The bandwidth allocation scheme introduced in this paper can be easily implemented in the existing MS/TP protocol with a slight modification. In this study, we actually developed the hardware and firmware of the modified MS/TP communication module in which the bandwidth allocation scheme is implemented. Using the modified MS/TP communication module, we developed an experimental model in order to examine the validity of the bandwidth allocation scheme in the MS/TP protocol. Experimental results show that the modified MS/TP protocol satisfies the requirements of real time communication for periodic and urgent messages of BACnet communication services.

• Proceedings of the Optical Society of Korea Conference
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• 2005.02a
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• pp.160-161
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• 2005

A critical issue in implementing efficient Ethernet passive optical network(EPON) System is the bandwidth allocation algorithm. The overall goal of bandwidth allocation is to effectively and fairly perform scheduling of time slots between ONUs in EPON System. We propose a new algorithm of dynamic bandwidth allocation for improved bandwidth efficiency in EPON system.

• ETRI Journal
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• v.26 no.2
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• pp.185-188
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• 2004

In this paper, we design a two-step scheduling algorithm to support multiple bandwidth allocation policies for upstream channel access in an Ethernet passive optical network. The proposed scheduling algorithm allows us a simultaneous approach for multiple access control policies: static bandwidth allocation for guaranteed bandwidth service and dynamic bandwidth allocation for on-demand, dynamic traffic services. In order to reduce the scheduling complexity, we separate the process of the transmission start- time decision from the process of grant generation. This technique does not require the timing information of other bandwidth allocation modules, so respective modules are free from a heavy amount of timing information or complex processing.