Current multimedia systems include many video streaming applications, of which, Client-Server structure is often used during early stages. The Client-Server structure operates smoothly as long as the streaming source remains stable and the bandwidth is sufficient. However, as multimedia systems can not keep pace with the accelerated pace at which the Internet is advancing, the P2P network structure has replaced the Client-Server structure to satisfy user requirements. A P2P live streaming system is characterized mainly by its savings in network bandwidth, ensuring that the bandwidth of a multimedia video streaming system does not limit future user growth. This fact implies that network bandwidth for user uploads can help to increase the external output bandwidth of a multimedia video streaming system. However, the efficiency of incorporating network bandwidth for user uploads in a multimedia video streaming system is limited in bandwidth owing to users’ terminal network. A larger number of users generally imply a stronger capacity for a multimedia system.
Used network bandwidth in a multimedia video streaming stream is monitored and detected using the OAM structure. The operational status of a multimedia system is thus determined based on its used network bandwidth. As the upload network bandwidth of a multimedia system is generally well known, whether the system has reached its upper network bandwidth limit can be determined by detecting and monitoring the used network bandwidth. However, for a P2P live video streaming system, its upper network bandwidth limit can not be represented based on its external traffic flow because users can provide their upload network bandwidths for the multimedia system, thus helping to share the upload network bandwidth of a multimedia system. Given this feature, the conventional OAM structure is inapplicable in P2P multimedia video streaming.
The conventional OAM system can detect only the network bandwidth of a multimedia system. However, for a P2P network, a user’s P2P performance and capabilities should be analyzed further to determine the operational status of a multimedia video streaming system in the P2P network. Therefore, this work presents a novel OAM scheme for a P2P multimedia video streaming system to determine the operational status of that system and the P2P operational status of users. The proposed OAM scheme can be integrated successfully with a multimedia system to acquire its operational information. The proposed scheme also includes message return feature in user ends. Moreover, the proposed OAM scheme accumulates information and messages for system analysis, allowing the subsequent analysis data to appear in a real-time graph chart.

現今的多媒體影音系統，應用在多媒上多數是應用於影音方面，在早期是採用Client-Server架構之系統。對於Client-Server系統架構而言，只要串流來源穩定及多媒體影音系統對外頻寬充足即可進行運作，然而由於網路的發展速度無法趕上多媒體影音系統發展速度，為了滿足使用者的需求，近年來已逐漸的由Client-Server架構轉變成P2P網路架構發展，對於使用P2P網路架構之多媒體影音系統，最大的好處在於網路頻寬的節省，使用者人數上的成長不再侷限於多媒體影音平台對外的頻寬，也就是利用使用者端之上傳網路頻寬來協助多媒體影音系統對外頻寬的彌補，但是使用者上傳網路頻寬的協助，對於多媒體影音系統的幫助，卻因為使用者末端網路的影響，所能給予的頻寬是有限制的。一般而言，若使用者人數越多，所能協助多媒體系統的能力則越強。
過去我們所看到採用Client-Server多媒體系統中，是採用偵測多媒體系統對外頻寬流量，利用其對外頻寬流量來判斷使用者運作狀態，通常來說，對於多媒體影音系統對外流量上限為已知之條件，藉由觀測其對外流量，來代表系統是否已達到運作上限。但是對於P2P多媒體影音系統而言，系統的對外流量並不代表系統的運作上限，由於使用者端會協助多媒體系統提供上傳網路頻寬，藉此幫助多媒體系統分擔對外流量，也因為有這樣的機制存在，過去的管理系統並無法適用於P2P多媒體影音架構。
在OAM系統而言，在使用P2P網路時，則必須要再更進一步去分析使用者的P2P行為能力，藉此得到多媒體影音系統在P2P網路下運作情形。因此OAM系統需要與多媒體影音系統結合，才能得知P2P影音多媒體運作狀態及使用者P2P運作狀態。在我們實作的OAM系統中，成功與多媒體系統結合，取得多媒體系統運作資訊，增加使用者端訊息回報，透過OAM系統收集，進行分析統計，並將分析數據以即時圖表的方式呈現，使我們可以了解到在P2P網路下使用者運作狀況及多媒體影音系統運作狀態。

[1] Jin-tae Oh; Dae-Young Kim; Hyup-Jong Kim, “A design of the OAM flow in the ring topology ATM networks”, IEEE International Conference on Communication Technology, Volume: 2, pp. 747-750, May 1996
[2] Garcia-Hernandez, J.; Ghanbari, M., “In-service monitoring of quality of service in ATM networks using OAM cells”, Journal of Applied Research and Technology, Vol.146,No.2, April 1999
[3] Jong-Dug Shin; Charcranoon, S.; Cankaya, H.C.; El-Bawab, T.S., “Procedures and functions for operation and maintenance in optical burst-switching networks”, Proceedings of the 2002 IEEE Workshop on IP Operations and Management (IPOM 2002), pp.149- 153, 2002
[4] Jeong-Dong Ryoo; Jongtae Song; Jaewoo Park; Bheom-Soon Joo,” OAM and its performance monitoring mechanisms for carrier Ethernet transport networks” Communications Magazine, Volume: 46, Issue: 3, pp. 97-103, IEEE, March 2008
[5] Wei-Jin Tzeng, “Design and Implementation of an IPv6 compatible P2P-based Live Streaming Delivering Platform, “, Master thesis, National Tsing Hua University, July 2009.
[6] Wei-Jen Huang, “A Platform-Independent and Portable Framework for Large Scale P2P System,” Master thesis, National Tsing Hua University, July 2009.
[7] RFC768 - User Datagram Protocol
[8] Yi-Ru Chen,” Design of a P2P Live Multi-Media Streaming System with Hybrid Push and Pull Mechanisms,” Master thesis, National Tsing Hua University, July 2009.
[9] Java, http://java.sun.com/
[10] MySQL, http://www.mysql.com/
[11] Fedora, http://fedoraproject.org/
[12] lighttpd, http://www.lighttpd.net/
[13] PHP, http://www.php.net/
[14] ChartDirector, http://www.advsofteng.com/
[15] AJAX, http://en.wikipedia.org/wiki/AJAX