彈性光網路是使用光的正交分頻複用(optical orthogonal frequency division multiplexing, O-OFDM)之技術，使頻譜能夠更加的靈活運用。當網路發生鏈路故障會造成大量資料丟失。群播保護在傳統的WDM網路上是一個重要的問題，到目前為止尚未有彈性光網路中之群播保護研究。因此本篇論文將針對彈性光網路上單鏈路故障之群播保護活存問題，提出兩個分段保護演算法分別為最低頻譜優先分段保護演算法(Low Spectrum First Segmented Protection Algorithms, LSF-SPA)和K樹的群播分段保護演算法(K-Tree Segmented Protection Algorithm, KT-SPA)。最低頻譜優先分段保護演算法會從低頻譜槽依序調整成本並找到群播樹和備份段，而K棵樹的群播分段保護演算法則會找K棵樹與備份段，然後選擇具有最少頻譜數之群播樹和備份段做配置。
實驗模擬於靜態網路之下，所提出的兩種方法在阻斷率和資源使用率是優於專用樹保護(Dedicated Tree Protection, DTP)、共享樹保護(Share Tree Protection, STP)、K棵樹之共享樹保護(K-Share Tree Protection, K-STP)。原因在於所提出之方法使用較少備份資源和較多共享資源達到保護。而KT-SPA之阻斷率也優於LSF-SPA。LSF-SPA時間複雜度為O(K(B-C+1)wn2)，KT-SPA時間複雜度為O((B-C+1)* wn2)， LSF-SPA擁有較低的時間複雜度。模擬於動態網路之下，LSF-SPA的阻斷率則是低於KT-SPA。

To make flexible use of spectrum, the optical orthogonal frequency division multiplexing (O-OFDM) technique is used in Elastic optical networks (EONs). When link-failure occurs in the network, it will cause huge information lost. Multicast protection is an important problem in the traditional WDM networks. But so far the multicast protection problem has not been studied in EONs. Therefore, in the article, the multicast protection problem is studied for the single link-failure case on the EONs. Two segment-based protection algorithms are proposed to solve this problem, they are Low Spectrum First Segmented Protection Algorithm (LSF-SPA) and K-Tree Segmented Protection Algorithm (KT-SPA). In LSF-SPA, the multicast tree and the backup segments are found by adjusting the cost of links on network, and wavelengths are allocated according to the sequence of spectrum slots. In KT-SPA, a set of K trees are generated, and then the primary tree and backup segments are found from the set that one with minimal number of spectrum slots.
The simulation results for static multicast requests show that the blocking ratio and resource utility ratio of KT-SPA and LSF-SPA are better than dedicated Tree Protection (DTP), Share Tree Protection (STP), and K-Share Tree Protection (K-STP). The reason is that the proposed algorithms can use less backup resources and more shared resources to protect. Blocking ratio of KT-SPA is better than LSF-SPA. Time complexity of KT-SPA is O(K(B-C+1)wn2) and Time complexity of LSF-SPA is O((B-C+1) wn2), LSF-SPA has a lower time complexity. The simulation results for dynamic multicast requests show that blocking ratio of LSF-SPA is better than KT-SPA.

中文摘要 I
Abstract II
誌謝 III
目錄 IV
圖目錄 VI
表目錄 X
第一章 導論 1
1.1 前言 1
1.2 彈性光網路介紹 1
1.3 彈性光網路頻譜配置 2
1.4 路由頻譜分配問題 3
1.5 群播(Multicast) 4
1.6 分段保護 5
1.7 研究動機 6
1.8 主要貢獻 6
1.9 後續章節介紹 6
第二章 問題定義 7
2.1 前提假設與已知 7
2.2 符號及相關參數 7
2.3 評估標準 8
2.4 研究限制與目標 9
第三章 文獻探討與分析 10
3.1 WDM網路單播保護 10
3.2 WDM網路單播分段保護 10
3.3 WDM網路群播保護 11
3.4 EON網路上路由頻譜分配問題 12
3.5 SLICE網路上路由頻譜分配問題 13
3.6 EON網路單播保護機制 13
3.7 EON網路群播路由 14
第四章 研究方法 15
4.1 基本概念與範例 15
4.2 群播分段保護的演算法 15
4.2.1 最低頻譜優先分段保護演算法(LSF-SPA) 15
4.2.2 K棵樹的分段保護演算法(KT-SPA) 22
第五章 實驗結果 31
5.1 模擬環境 31
5.2 靜態網路模擬 32
5.2.1 模擬最低頻譜優先演算法(LSF-SPA)於靜態網路 34
5.2.2 模擬K棵樹的群播分段保護演算法(KT-SPA)於靜態網路 39
5.2.3 DTP、STP、K-STP、 LSF-SPA和KT-SPA相互比較於靜態網路........ 43
5.2.4 LSF-SPA和KT-SPA在靜態網路上比較網路破碎情況 47
5.3 動態網路模擬 50
5.3.1 LSF-SPA和KT-SPA在動態模擬比較阻斷率 51
5.3.2 LSF-SPA和KT-SPA在動態模擬比較資源使用率 57
第六章 結論與後續研究 62
6.1 結論 62
6.2 後續研究 62
參考文獻 63

圖目錄
圖1-1 (a)Single Light Rate WDM, (b) elastic optical networks 2
圖1-2 (a)三個節點的網路, (b)圖1-2(a)頻譜使用情況 3
圖1-3有分光能力的WDM網路群播請求之傳送 4
圖1-4群播請求在網路上分段保護的例子 5
圖4-1 LSF-SPA流程圖 18
圖4-2 (a) 6個節點網路,(b)鏈路使用頻譜情況 19
圖4-3 (a)第1個頻譜槽到第2個頻譜槽上使用公式1調整成本, (b)第2個頻譜槽到第3個頻譜槽上使用公式1調整成本 19
圖4-4 群播樹依照分支節點和目的節點分段 20
圖4-5 (a)調整主要段1到2之成本並找出備份段, (b)調整主要段1到4之成本並找出備份段 20
圖4-6使用LSF-SPA演算法配置結果 21
圖4-7 KT-SPA流程圖 24
圖4-8 (a) 6個節點網路, (b)鏈路使用頻譜情況 25
圖4-9 (a)第一顆群播樹, (b)第二顆群播樹, (c)第二顆群播樹, (d)最後一顆群播樹 25
圖4-10三棵群播樹依照分支節點和目的節點分段 26
圖4-11第1顆樹無法放入第1到第2頻譜中 27
圖4-12第一棵群播樹放入到第二和第三的頻譜,(a)找出1-2之備份段, (b)找出1-6-4之備份段 27
圖4-13第一顆群播樹放入到第三和第四的頻譜中(a)找出1-2之備份段, (b)找出1-6-4之備份段 28
圖4-14 第二棵群播樹放入(a)第一和第二頻譜中, (b)第二和第三頻譜中 28
圖4-15第2顆樹放入第3到第4頻譜中 (a)找出1-2之備份段, (b)找出1-5-4之備份段 29
圖4-16最後一棵群播樹放入 (a)第一和第二頻譜中, (b)第二和第三頻譜中 29
圖4-17第3顆樹放入第3到第4頻譜中 30
圖4-18最後配置第1顆樹放入第3到第4頻譜中 30
圖 5-1 COST 239網路拓樸 31
圖 5-2 USNET網路拓樸 32
圖5-3 LSF-SPA比較其阻斷率於COST239 34
圖5-4 LSF-SPA比較其阻斷率於USNET 34
圖5-5 LSF-SPA比較其執行時間於COST239 35
圖5-6 LSF-SPA比較其執行時間於USNET 35
圖5-7 LSF-SPA比較其資源使用率於COST239 36
圖5-8 LSF-SPA比較其資源使用率於USNET 36
圖5-9 LSF-SPA比較其頻譜效能比率於COST239 37
圖5-10 LSF-SPA比較其頻譜效能比率於USNET 37
圖5-11 KT-SPA比較其阻斷率於COST239 39
圖5-12 KT-SPA比較其阻斷率於USNET 39
圖5-13 KT-SPA比較其執行時間於COST239 40
圖5-14 KT-SPA比較其執行時間於USNET 40
圖5-15 KT-SPA比較其資源使用率於COST239 41
圖5-16 KT-SPA比較其資源使用率於USNET 41
圖5-17 KT-SPA比較其頻譜效能比率於COST239 42
圖5-18 KT-SPA比較其頻譜效能比率於USNET 42
圖5-19 COST239網路阻斷率比較 43
圖5-20 USNET網路阻斷率比較 43
圖5-21 COS239網路執行時間比較 44
圖5-22 USNET網路執行時間比較 44
圖5-23 COST239網路資源使用率比較 45
圖5-24 USNET網路資源使用率比較 45
圖5-25 COST239網路頻譜使用比率比較 46
圖5-26 USNET網路頻譜使用比率比較 46
圖5-27 LSF-SPA比較整體網路破碎情況於COST239 47
圖5-28 LSF-SPA比較整體網路破碎情況於USNET 48
圖5-29 KT-SPA比較整體網路破碎情況於COST239 48
圖5-30 KT-SPA比較整體網路破碎情況於USNET 49
圖5-31 LSF-SPA比較改變單位時間間隔於COST239 51
圖5-32 LSF-SPA比較改變單位時間間隔於USNET 51
圖5-33 KT-SPA比較改變單位時間間隔於COST239 52
圖5-34 KT-SPA比較改變單位時間間隔於USNET 52
圖5-35 LSF-SPA比較改變持續時間於COST239 53
圖5-36 LSF-SPA比較改變持續時間於USNET 53
圖5-37 KT-SPA比較改變持續時間於COST239 54
圖5-38 KT-SPA比較改變持續時間於USNET 54
圖5-39 LSF-SPA比較改變卜松分佈每單位時間平均抵達率於COST239 55
圖5-40 LSF-SPA比較改變卜松分佈每單位時間平均抵達率於USNET 55
圖5-41 KT-SPA比較改變卜松分佈每單位時間平均抵達率於COST239 56
圖5-42 KT-SPA比較改變卜松分佈每單位時間平均抵達率於USNET 56
圖5-43 LSF-SPA改變單位時間比較資源使用率於COST239 57
圖5-44 KT-SPA改變單位時間比較資源使用率於COST239 57
圖5-45 LSF-SPA改變單位時間比較資源使用率於USNET 57
圖5-46 KT-SPA改變單位時間比較資源使用率於USNET 58
圖5-47 LSF-SPA改變持續時間比較資源使用率於COST239 58
圖5-48 KT-SPA改變持續時間比較資源使用率於COST239 59
圖5-49LSF-SPA改變持續時間比較資源使用率於USNET 59
圖5-50 KT-SPA改變持續時間比較資源使用率於USNET 59
圖5-51 LSF-SPA改變每單位平均抵達率比較資源使用率於COST239 60
圖5-52 KT-SPA改變每單位平均抵達率比較資源使用率於COST239 60
圖5-53 LSF-SPA改變每單位平均抵達率比較資源使用率於USNET 61
圖5-54 KT-SPA改變每單位平均抵達率比較資源使用率於USNET 61

表目錄
表5-1 平均LSF-SPA資源使用率 38
表5-2 平均LSF-SPA頻譜效能比率 38

[1] G. Zhang, M. D. Leenheer,A. Morea,and B. Mukherjee, “A survey on OFDM-based elastic core optical networking, ”Communications Surveys &; Tutorials, Vol. 15, No. 1, pp. 5-87, Quarter 2013.
[2] L. Guo, H. Yu and L. Li, “Segment shared protection for survivable meshed WDM optical networks, ”Optics Communications, Vol. 251, No. 4-6, pp. 28-338, July 2005.
[3] J. Cao, L. Guo, H. Yu, and L. Li, “A novel recursive shared segment protection algorithm in survivable WDM networks,” Journal of Network and Computer Applications, Vol. 30, No. 2, pp. 77–694, April 2007.
[4] P. H. HoandH. T. Mouftah, “A novel survivable routing algorithm for shared segment protection in mesh WDM networks with partial wavelength conversion, ”Journal on IEEE, Selected Areas in Communications, Vol. 2, No. 8, pp. 548-1560, October 2004.
[5] N. H. Bao, Z. Z. Zhang,L. M. Li, Hong-Fang Yu, and Hong-Bin Luo, “A hybrid protection strategy based on node-disjointness against double failures in optical mesh networks, ”Photonic Network Communications, Vol. 22, No. 1, pp. 3-22, August 2011.
[6] D. R. Din and S. L. Tung, “The backup reprovisioning problem of NEPCs on survivable WDM networks, ”Optical Fiber Technology, Vol. 8, No. 3, pp. 21-130, May 2012.
[7] B. Jaumard and H. Li, “Segment p-cycle design with full node protection in WDM mesh networks,” in Proc. of 2011 18th IEEE Workshop on Local &; Metropolitan Area Networks (LANMAN), Chapel Hill, NC, pp.1-6, October 2011.
[8] S. Sebbah and B. Jaumard, “An efficient column generation design method of p-cycle-based protected working capacity envelope,” Photonic Network Communications, Vol. 24, No. 3, pp.167-176, December 2012.
[9] A. Haque, P. H. Ho, andH. M. K. Alazemi, “Inter group shared protection (I-GSP) for survivable WDM mesh networks, ”Optical Switching and Networking, Vol. 10, No. 2, pp.119-131, April 2013.
[10] S. Sebbah and B. Jaumard, “Differentiated quality-of-protection in survivable WDM mesh networks using p-structures, ”Computer Communications, Vol. 36, No. 6, pp. 621-629, March 2013.
[11] X. Shao, Y. K. Yeo, Y. Bai, J. Chen, L. Zhou, and L. H. Ngoh, “Backup reprovisioning after shared risk link group (SRLG) failures in WDM mesh networks, ”IEEE/OSA Journal of Optical Communications and Networking, Vol. 2, No. 8, pp.587-599, August 2010.
[12] L. Long and A. E. Kamal, “Tree-based protection of multicast services in WDM mesh networks,” in Proc. of 2009 Conference on Global Telecommunications (GLOBECOM), Honolulu, HI, pp.1-6, November 2009.
[13] T. Feng, L. Ruan, C. Wang, and H. Qin, “PXT-based path protection for multicast sessions in WDM networks, ” in Proc. of Sarnoff Symposium, Princeton, NJ, pp.1-5, April 2010.
[14] C. Lu and L. Li, “Shared protection in multicast optical networks,” in Proc. of 2008 Communications Conference on International, Circuits and Systems, Fujian, China, pp.577-581, May 2008.
[15] Z. J. Zhu, W. Dong, Z.C. Le, and Xingshu Sun, “A novel segment protection with segment route scheme in multicasting survivable networks,” in Proc. of Communications and Photonics Conference and Exhibition (ACP), Shanghai, China, pp.1-7, November 2009.
[16] C. Lu, H. Luo, S. Wang, and L. Li, “A novel shared segment protection algorithm for multicast sessions in mesh WDM networks,” ETRI Journal, Vol. 28, No. 3, pp.329-336, June 2006.
[17] L. Liao, L. Li, and S. Wang, “Multicast protection scheme in survivable WDM optical networks,” Journal of Network and Computer Applications, Vol. 31, No. 3, pp.303–316, August 2008.
[18] T. Feng, L. Ruan, and W. Zhang, “Intelligent p-cycle protection for dynamic multicast sessions in WDM networks, ”IEEE/OSA Journal of Optical Communications and Networking, Vol. 2, No. 7, pp.389-399, July 2010.
[19] D. R. Din, and J. Y. Jiang, “Delay-constrained survivable multicast routing problem in WDM networks,” Computer Communications, vol. 35, No. 10, pp.1172–1184, June 2012.
[20] A. Gadkar, J. Plante, and V. Vokkarane, “Static multicast overlay in WDM unicast networks for large-scale scientific applications, ”in Proc. of UMass Dartmouth CIS Technical Reports, North Dartmouth, MA, pp.1-14, March 2011.
[21] Z. Zhu, W. Lu, L. Zhang, and N. Ansari, “Dynamic service provisioning in elastic optical networks with hybrid single-/multi-path routing,” Journal of Lightwave Technology,Vol. 31, No. 1, pp.15-22, January 2013.
[22] M. Klinkowski, “A genetic algorithm for solving RSA problem in elastic optical networks with dedicated path protection,” in Proc. of International Joint Conference on CISIS’12-ICEUTE´12-SOCO´12 Special Sessions, Warsaw,Poland, Vol. 189, pp.167-176, 2013.
[23] Y. Wang, X. Cao, and Y. Pan, “A study of the routing and spectrum allocation in spectrum-sliced elastic optical path networks, ”in Proc. of 2011 IEEE International Conference on Computer Communications (INFOCOM), Shanghai, China, pp.1503-1511, April 2011.
[24] T. Takagi, H. Hasegawa, K. Sato, Y. Sone, B. Kozicki, A. Hirano, and M. Jinno, “Dynamic routing and frequency slot assignment for elastic optical path networks that adopt distance adaptive modulation, ”in Proc. of Optical Fiber Communication Conference and Exposition (OFC/NFOEC), Los Angeles, pp.1-3, March 2011.
[25] J. Zhang, C. Lv, Y. Zhao, B. Chen, X. Li, S. Huang, and W. Gu, “A novel shared-path protection algorithm with correlated risk against multiple failures in flexible bandwidth optical networks,” Optical Fiber Technology, Vol. 18, No. 6, pp.532-540, December 2012.
[26] S. Kosaka, H. Hasegawa, K. I. Sato, T. Tanaka, A. Hirano, and M. Jinno, “Shared protected elastic optical path network design that applies iterative re-optimization based on resource utilization efficiency measures, ”in Proc. of European Conference and Exhibition on Optical Communication, Amsterdam, Netherlands, pp.1-3, September 2012.
[27] M. Klinkowski, and K. Walkowiak, “Offline RSA algorithms for elastic optical networks with dedicated path protection consideration, ” in Proc. of 2012 4th International Congress on Ultra Modern Telecommunications and Control Systems and Workshops (ICUMT), Petersburg, Russia, pp.670-676, October 2012.
[28] Y. Wei and G. Shen, “Span restoration for flexi-grid optical networks under different spectrum conversion capabilities, ”in Proc. of 2013 9th International Conference on Design of Reliable Communication Networks (DRCN), Budapest, Hungary, pp.79-87, March 2013.
[29] L. Gong, X. Zhou, X. Liu, W. Zhao, W. Lu, and Z. Zhu, “Efficient resource allocation for all-optical multicasting over spectrum-sliced elastic optical networks,” IEEE/OSA Journal of Optical Communications and Networking, Vol. 5, No. 8, pp.836 -847, August 2013.
[30] X. Liu, L. Gong, and Z. Zhu, “On the spectrum-efficient overlay multicast in elastic optical networks built with multicast-incapable switches,” IEEE Communications Letters, Vol. 17, No. 9, pp.1860-1863, September 2013.