國
立 政 治 大 學
‧
N a tio na
l C h engchi U ni ve rs it y
at 9.5 ~ 9.8 “UDP/Traffic stop "
at 9.9 “Multicast service stop"
在 1.0 秒時開始 Join 到 Multicast Group，以及在 4.0 秒到 4.1 秒時發生 Handover，
Receiver 從 M2 移動到 M4，又在 7.0 秒到 7.1 秒時發生 Handover，Receiver 從 M4 移動 到 M6。
4.4 數據分析與比較
依據以上的模擬參數，我們得到了以下的模擬結果，首先來看在 Throughput 方面 的表現，請參看圖 4.3 ，從圖中曲線可看出 CLIMP 在 Throughput 方面的表現還是優於 SSM，那是因為 CLIMP 比 SSM 多了一些 Congestion Control 的機制，包括 Packets Scheduling 和 Rule Filter，這點在 Traffic Loading 較高時會比較明顯，但畢竟是基 於 SSM 的 Routing 方式來強化其原來的應用，所以在整體 Throughout 上的效益並沒有 高出很多，約高出 12.5%。，但是可以看出在每次的 Handover 發生時，Throughout 一 開始一樣都會掉下來一些，可是 CLIMP 很快的就會恢復原有的傳輸水準，那是因為有 CS 協助 Caching Data 的關係，使得不單是對 Throughout 有幫助，對 Delay 和 Jitter 更是有顯著的影響。
‧ 國
立 政 治 大 學
‧
N a tio na
l C h engchi U ni ve rs it y
圖 4.3 Simulation for Throughput 再來比較 Delay 的影響， 如下圖 4.4 所示 :
採用 Application Layer 的 Multicasting 方案，在 Delay 的表現通常會比較不理想，
因為 Application Layer 對低層傳輸狀況的反應較慢，比較無法及時修正傳輸參數。所 以一旦發生 Packet Loss 時，就必須重傳或是直接利用錯誤修正的方式以一個正常的 Multicast Packet 加上修正用 Packets 來當做每次要傳送的 Packets，但額外的修正 Packets 也會消耗頻寬，必須審慎評估，大部份都會要求重傳(Retransmission)，生成 樹狀結構的協定在重傳上有時候比較具有優勢，因為本來資料就是都由 Root Node 來轉 發，是故加強在 Root Node 的重傳功能會使 Delay 的影響變小，因此 CLIMP 利用 CS 來當 Data Buffer，一有重傳需求發生時 CS 就會把需重傳的資料轉發出去。一開始時 會因為 Data Buffer 的 Hit Ratio 做一些 Queuing Size 的調整，慢慢的就會發生效果 使 Delay 有所降低。再者因為 CS 對網路的 Congestion 情況也有一些調節功能，雖然
‧ 國
立 政 治 大 學
‧
N a tio na
l C h engchi U ni ve rs it y
比不上底層的協定有效率，但是還是有一定程度的幫助。如圖中的結果所示，一開始 CS 對網路的情況做一些適應上的調整，之後就比較穩定了，以平均來看 CLIMP 比 SSM 降低 了 34.6%。
圖 4.4 Simulation for Delay 最後來看 Jitter 的表現如何， 請參看 圖 4.5 所示 :
Jitter 的發生和 Router 中對 Packet Queuing 的效能有直接的影響，所以由 CLIMP 對減 少 Delay 的作為同樣的也對 Jitter 的情況產生正面的影響，使得 CLIMP 在 Jitter 上 的表現整體來看也比 SSM 來的理想，但是因為 Application Layer 對低層的網路現況的 反應比較慢也使得 Jitter 的幅度大了些，但是以平均值來看，大約比 SSM 降低 66.7%。
‧ 國
立 政 治 大 學
‧
N a tio na
l C h engchi U ni ve rs it y
圖 4.5 Simulation for Jitter
‧
SSM搭配屬於Network Layer的Agent再由Application Layer來統籌管理，由模擬的數據 可以看出是一項不錯的解決方案，所以本論文的貢獻是 : 用Communication Control Agent來提供對Congestion的控制。三、一般的Multicasting都是Source端被動式的轉發資料(Pull的方式)，我們 嘗試以Push的方式來轉發Multicasting資訊，當然這必須要考慮所Push的 資訊是否為Receiver所需要，不然也只是增加網路的開銷，至於如何加強 和Receiver間的互動也是未來值得探討的問題。
四、單純使用Application Layer Multicasting 或Network Layer
Multicasting 都無法使得Multicasting的效能達到最佳化，必須同時考 慮網路的傳輸條件和傳輸資料內容的特性才能有較可靠的資料傳輸，本論
‧ 國
立 政 治 大 學
‧
N a tio na
l C h engchi U ni ve rs it y
文提出由 Network Layer搭配Application Layer的Cross Layer設計，在 Throughput 及 Delay和Jitter的整體來看都有不錯的表現。
另外還有一個對Multicasting的協定來說也是很重要的考慮因素的是可擴展性，
有相關著作提出一些如何將Ad Hoc環境中的Multicasting擴展應用到Internet上的作法 [43]，這也是很重要的一環，畢竟任何網路相關的研究都不能不正視和Internet間的互 操作性。
‧
【1】S. Deering. Host Extensions for IP Multicasting. IETF RFC 1112, August 1989.
【2】Defense Advanced Research Projects Agency Information Processing Techniques Office. INTERNET PROTOCOL. IETF RFC 791, September 1981.
【3】S. Bhattacharyya. An Overview of Source-Specific Multicast. IETF RFC
3569, July 2003.【4】Y. Chu, S.G. Rao, and H. Zhang. A Case for End System Multicast. In
Proceedings of ACM Sigmetrics, June 2000, 1-12.【5】Luo Junhai, Ye Danxia, Xue Liu and Fan Mingyu. A survey of multicast routing protocols for mobile ad-hoc networks. IEEE Communications
Surveys & Tutorials, vol. 11, no. 1, pp. 78-91, January 2009【6】
，B. Fenner, M. Handley, H. Holbrook and I. Kouvelas. Protocol
Independent Multicast - Sparse Mode. IETF RFC 4601, August 2006.
【7】A. Ballardie. Core Based Trees (CBT) Multicast Routing Architecture.
IETF RFC 2201, September 1997.
【8】C. Hedrick. Routing Information Protocol. IETF RFC 1058, June 1988.
【9】C. Hedrick. Telnet Terminal Speed Option. IETF RFC 1079, December 1988.
【10】A. Adams, J. Nicholas and W. Siadak. Protocol Independent Multicast -
Dense Mode (PIM-DM). IETF RFC 3973, January 2005.
‧
【11】J. Moy. Multicast Extensions to OSPF. IETF RFC 1584, March 1994.
【12】E. Bommaiah, M. Lui, A.MCAuley, and R.Talpade. AMRoute: Ad Hoc Multicast Routing Protocol. Internet Draft, draft-manet-amroute-00.txt, Aug 1998
【13】C.W. Wu, Y.C. Tay. AMRIS: A Multicast Protocol for Ad hoc Wireless Networks. Military Communications Conference Proceedings, 1999.
MILCOM 1999. IEEE. Oct 1999, 25-29 vol.1
【14】Elizabeth M. Royer, and Charles E. Perkins. Multicast Ad hoc On-Demand Distance Vector (MAODV) Routing. Internet Draft,
draft-ietf-manet-maodv-00.txt, July 2000【15】C. Perkins, E. Belding-Royer, and S. Das. Ad hoc On-Demand Distance Vector (AODV) Routing. IETF RFC 3561. July 2003
【16】Kumar Viswanath, Katia Obraczka, Member, IEEE, and Gene Tsudik.
Exploring Mesh and Tree-Based Multicast Routing Protocols for
MANETs. Mobile Computing, IEEE Transactions on Volume 5, Issue 1, Jan. 2006, Page(s): 28 - 42
【17】M. Gerla, G. Pei, S.J. Lee, and C.C. Chiang. On-Demand Multicast Routing Protocol (ODMRP) for Mobile Ad-Hoc Networks. Internet
Draft, draft-ietf-manet-odmrp-00.txt. November 1998【18】Chao Gui and Prasant Mohapatra. Efficient Overlay Multicast for Mobile Ad Hoc Networks. Wireless Communications and Networking, 2003.
WCNC 2003. 2003 IEEE. March 2003 , On page(s): 1118-1123 vol.2
【19】 S. Corson, and J. Macker. Mobile Ad hoc Networking (MANET):
‧
Routing Protocol Performance Issues and Evaluation Considerations.
IETF RFC 2501, January 1999
【20】S. Voulgaris and M. van Steen. Hybrid dissemination:Adding
determinism to probabilistic multicasting in largescale p2p systems. In
Middleware 2007, ACM/IFIP/USENIX 8th International Middleware Conference, Proceedings. Springer, 2007, pp. 389–409, 2007.【21】S. Zahoor Ul Huq et. Al, EMMR: A Multicast Routing Protocol for Mobile Ad Hoc Networks, International Journal of Computer Science
and Network Security, vol. 9, no. 4 , April 2009【22】Ogier, R. MANET Extension of OSPF Using CDS Flooding. Proceedings
of the 62nd IETF, March 2005. http://www3.ietf.org/proceedings/05mar/slides/ospf-5/sld1.htm. 2005.
【23】S. Bhattacharyya, An Overview of Source-Specific Multicast (SSM) . IETF RFC 3569, July 2003
【24】B. Fenner, and D. Meyer. Multicast Source Discovery Protocol (MSDP).
IETF RFC 3618, October 2003
【25】T. Camilo, J. Sá Silva, F. Gaudêncio and F. Boavida. A new SSM approach for mobile environments. The 7th IFIP International
Conference on Mobile and Wireless Communication Networks, 2005【26】Sangjin Jeong, Myung-Ki Shin, and Hyoug-Jun Kim. Design,
Implementation and Evaluation of Source-Specific Multicast System
over IPv6 Networks. Advanced Communication Technology, 2006.
‧
ICACT 2006. The 8th International Conference, Feb. 2006, Volume: 3,
On page(s): 4 pp.-2003
【27】Silva, J.S.; Duarte, S.; Monteiro, E.; Boavida, F. MNet - a new multicast approach for the future Internet. Telecommunications, 2003. ICT 2003.
10th International Conference on Volume 1, Issue , March 2003 Page(s):
340 - 347 vol.1
【28】Christian Hubsch and Oliver P. Waldhorst : Enhancing Application-Layer Multicast Solutions by Wireless Underlay Support. Institute for
Telematics, University of Karlsruhe (TH), Germany【29】Banerjee, S., Bhattacharjee, B., Kommareddy, G.: Scalable Application Layer Multicast. Proc. SIGCOMM 2002, Pittsburgh, PA, USA, 2002.
pages 205~217
【30】Mihaela van der Schaar, Sai Shankar N, Cross-layer wireless multimedia transmission: Challenges, principles and new paradigms, IEEE Wireless
Communications, vol. 12, no. 4, Aug 2005 pp. 50-58【31】Peter Baumung, TrAM: Cross-layer efficient application-layer multicast in mobile ad-hoc networks, WCNC 2007 - IEEE Wireless
Communications and Networking Conference, no. 1, March 2007 pp.3878-3882
【32】Oh, Soon Y. Gerla, Mario Zhao, Pengkai Daneshrad, Babak Pei,
Guangyu Kim, Jae H. MIMO-CAST: A Cross-Layer Ad Hoc
Multicast Protocol using MIMO Radios. Military Communications
Conference, 2007. MILCOM 2007. IEEE. Oct. 2007, On page(s): 1-6‧
【33】Reuven Cohen, Guy Grebla and Liran Katzir. Cross-Layer Hybrid FEC/ARQ Reliable Multicast With Adaptive Modulation and Coding in Broadband Wireless Networks. IEEE/ACM Transactions on Networking,
vol. 18, no. 6, December 2010【34】A. Sabari, K. Duraiswamy, Ant Based Adaptive Multicast Routing Protocol (AAMRP) for Mobile Ad Hoc Networks. International Journal
of Computer Science and Network Security, vol.6, no. 2, 2009【35】Kurup, G. Sekercioglu, Y.A. Mani, N. Source Specific Multicast (SSM) Group Management Analysis Framework for the Next Generation Mobile Internet. Next Generation Internet Networks 2005, April 2005, On page(s): 420- 425
【36】Dunstan Adam, DiBurro Larry, and Li Yunhou, Method and apparatus for forwarding multicast data by relaying IGMP group membership,
Patent number US6654371 B1, Issued on November 25, 2003.【37】W. Fenner. Internet Group Management Protocol. IETF RFC 2236, November 1997
【38】Bill Fenner, Haixiang He, Brian Haberman, Hal Sandick,
IGMP/MLDbased Multicast Forwarding (IGMP/MLD Proxying),
Internet Draft, draft-ietf-magma-igmp-proxy-06.txt, April, 2004【 39 】 Romdhani, I.; Munoz, J.; Bettahar, H.; Bouabdallah, A. Adaptive Multicast Membership Management for Mobile Multicast Receivers.
Wireless and Mobile Computing, Networking and Communications,
‧ 國
立 政 治 大 學
‧
N a tio na
l C h engchi U ni ve rs it y
2006. (WiMobapos;2006). IEEE International Conference on Volume , Issue , 19-21 June 2006 Page(s):189 - 195
【40】Jiunn-Ru Lai; Wanjiun Liao; Ming-Yu Jiang; Chien-An Ke. Mobile multicast with routing optimization for recipient mobility.
Communications, 2001. ICC 2001. IEEE International Conference on Volume 5, Issue , 2001 Page(s):1340 - 1344 vol.5
【41】Xiaohua Tian, Yu Cheng and Xuemin (Sherman) Shen. DOM: A Scalable Multicast Protocol for Next-Generation Internet.
IEEE Network, vol. 24, no. 4, July 2010.【42】T. Camilo, J. Silva, F. Boavida, “Enabling NS-2 with SSM Enviroments”,
< http://eden.dei.uc.pt/~tandre/ssm_extension/index.htm >, 2004
【43】Abduljalil, F.M. Bodhe, S.K. A SURVEY OF INTEGRATING IP MOBILITY PROTOCOLS AND MOBILE AD HOC NETWORKS. :
Communications Surveys & Tutorials, IEEE Publication Date: First Quarter 2007 Volume: 9, Issue: 1 , On page(s): 14-30