正交分頻多工網路中考量服務等級協議之適性化資源分配演算法

An Adaptive Resource Allocation Algorithm in OFDMA Networks Considering Service Level Agreement

邱瑞益(Ruei-Yi Chiu)

指導教授 ： 林志浩

中原大學/商學院/資訊管理學系/碩士(2005年)

https://doi.org/10.6840/CYCU.2006.00447

摘要

無線網路傳輸的服務，已經由早期的文字傳輸，提昇到現今多媒體應用的等級了，因此高速資料的傳輸需求也相對增加，然而可以使用的頻寬資源仍然有限，為了增加頻寬資源的使用效率，同時保證使用者不同的服務品質(QoS)要求，就需要一套有效的資源分配方法進行頻寬資源的管理。
而在無線資源管理的相關文獻中，並未考量到使用者在傳送資料時對於頻寬資源的需求程度，加上使用者所傳送的資訊不再侷限於語音、文字類型的非即時(nonreal-time)資料流，而是結合了影像等多媒體資訊，對於這些即時性(real-time)的服務，就需要分配更大量的頻寬來滿足使用者的需求或是優先處理，在做資源分配時，應針對使用者不同類型的服務需求給予不同的資源分配模式。
本研究提出一有效的資源分配方法(LR-based Algorithm)，考量使用者的服務類型進行頻寬資源的管理，目的在滿足使用者服務品質的需求及使用功率等相關限制下，使系統傳輸速率達到最大，同時服務提供者能夠獲得最大的收益；能提供無線通訊網路業者在面對WiMAX網路資源規劃與管理之困境，我們深入地探討並且提供網路效能、構建與營運成本控制之技術，同時加入了服務等級協議(Service Level Agreement; SLA)的考量，利用數學最佳化技巧為基礎之方略，對於服務提供者的頻寬資源，提供一個分配策略的參考方針，使得服務提供者在面對WiMAX網路資源管理的問題時，可以有一準則可依循。
研究結果得知隨著使用者數量的增加，LR-based Algorithm仍能夠對有限的頻寬資源做更有效率的分配，滿足了使用者的服務品質(QoS)需求，同時服務提供者也能夠獲得較佳的收益。

關鍵字

資源分配 ； 服務品質 ； 服務等級協議 ； 數學最佳化 ； 正交分頻多工

並列摘要

Wireless network transmission service, mainly handling textual transmission in the old days, has entered the epoch of multimedia application. Consequently, the demand for high data rate transmission has increased. Nevertheless, the available bandwidth is still limited. To enhance the efficiency of bandwidth utilization, as well as to satisfy users with diverse demands for quality of service (QoS), a resource allocation method, capable of efficacious bandwidth management, is needed.
Previous literature regarding wireless resource management, however, does not consider the different demands of users for QoS in the process of data transmission. Additionally, rather than merely containing non real-time service, such as voice and texts, transmitted data also include real-time information, such as multimedia data stream. Hence, distinct models of resource allocation are needed to meet different demands of users.
This research proposes an effective LR-based Algorithm, which has taken into account the service types of users, power usage and other restrictions, and aims to satisfy diverse demands of users, as well as to maximize data transmission rates and the revenues of service providers. In addition, this proposal has explored the techniques with regard to network efficacy, network construction, and operation cost management. It has also taken the Service Level Agreement (SLA) into consideration and applied methods based on mathematical optimization, purposing to provide a solution to the dilemma faced by service providers concerning the planning and management of WiMAX networks.
The result of this research shows that even when the number of users increases, the LR-based Algorithm can still efficiently allocate limited bandwidth resource. The proposed algorithm also satisfies the QoS of users and benefits service providers in increasing their revenue.

並列關鍵字

Lagrangean Relaxation ； Resource Allocation ； QoS ； Mathematical Optimization ； Service Level Agreement ； Orthogonal Frequency Division Multiplexing

參考文獻

[1] Alasti, M., Farrokhi, F.R., Olfat, M. and Liu, K.J.R., “Service level agreement(SLA) based scheduling algorithms for wireless networks,” IEEE International Conference on Communications, vol. 2, 2004, pp. 1028-1032.

[2] Engels, M., “Wireless OFDM Systems: How to Make Them Work?,” Kluwer Academic Publishers, 2002

[3] Ergen, M., Coleri, S. and Varaiya, P., “QoS aware adaptive resource allocation techniques for fair scheduling in OFDMA based broadband wireless access systems,” IEEE Transactions on Broadcasting, vol. 49, no. 4, 2003, pp. 362-370.

[4] Farrokhi, F.R., Olfat, M., Alasti, M. and Liu, K.J.R., “Scheduling algorithm for quality of service aware OFDMA wireless systems,” IEEE Global Telecommunications Conference, vol. 4, 2004, pp. 2689-2693.

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