都會區寬頻通訊網路技術與趨勢之評估

Abstract

電信自由化、網際網路IP應用的成長，以及無線行動通訊的普及，使電信產業在過去幾年中產生大幅成長。電信製造業者由於網路建設的需求不斷地增加，其營運收入也跟著呈現出大幅成長。由電信業營運商及製造商在2000年底前的股票市值，可以明顯的看出電信產業的繁榮景象。然而，在2000年底電信產業突然不景氣，使資本支出明顯的減少，促使電信產業的產業結構產生劇烈的改變與重組。本研究分析影響電信產業商業活動之助力與阻力，並探討電信及網際網路dot-com產業泡沫化過程的教訓，進一步討論未來電信產業存在的主要商機。 在電信產業不景氣的時期，全球網際網路的數據使用量仍然持續的成長，尤其是大量企業用戶開始使用乙太網路 (100M/s、1/10 Gb/s)，使企業內部的數據話務量極速的成長。不僅如此，中小企業及一般住戶使用ADSL及銅纜數據機的普及率不斷提高，更是促進數據業務成長的主要動力。 目前都會區網路主要是使用SONET/SDH的設備來「集中」傳送數據資料。但是由於SONET/SDH在傳輸數據時，會限制頻寬及使用的彈性，因此限制了都會網路的發展，所以需要尋找新的都會區網路接續解決方案來滿足目前的需求。由於乙太網路的技術簡單、成本低、容易聯通網路、容易處理IP數據、與服務提供快速的優點，再加上新發展的乙太網路Gigabit介面可以擴增至大區域(WAN)的通訊功能，因此使得Gigabit乙太網路成為滿足都會區寬頻需求最可能的解決方案。 本研究探討Gigabit乙太網路的進展、分析Gigabit乙太網路使用於都會網路的優缺點，並探討技術演進對電信業者的影響。本研究使用模糊多評準決策(Fuzzy MCDM)方法來評估何種解決方案最合適於都會區寬頻通訊的需求。研究結果顯示SONET/SDH 其多目標之效用值較Gigabit乙太網路為高。 電信自由化使電信產業在長途、國際及行動通信業務上產生越來越多的競爭，但是在區域迴路(Local Loop)的部分卻一直缺乏競爭，這種不健全的產業競爭現象，促使各國在制訂電信法規時，著重於研究如何鼓勵區域迴路的競爭，本研究分析不同的新接續技術及政府政策。研究分析結果發現，光纖能提供足夠的頻寬、使用WLAN及WiMAX可以滿足移動寬頻；而政策法規的規範上則傾向於建議無法與現有的電信商競爭的新電信業者可以進行整合，與現有的區域迴路業者進行合理的競爭。

Telecommunications deregulation, the exponential increase in Internet IP applications, and the popularity of mobile services have created tremendous growth in the telecommunications service industry in the past few years. With unprecedented demands on network infrastructure, telecommunications equipment manufacturers also enjoyed sales and revenue growth until the economic downturn toward the end of the year 2000. The prosperity of telecommunications service providers and equipment manufacturers were reflected notably on their respective stock performances. However, the abrupt slowdown, particularly in capital spending on networking equipment, has resulted in mass corporate restructuring and workforce realignment in the telecommunications industry. In this study, we have analyzed the “business drivers and draggers” that caused the telecommunications boom and downturn. In this context, we review lessons learned from the dot-com implosion and the downturn in the global telecommunications industry. We also discuss the telecom industry’s latest developments in preparation for the next wave of business opportunities. Despite the telecom industry downturn, global Internet traffic growth continues to create bandwidth demand in the telecommunications network. As 100 Mb/s Ethernet and 1/10 Gigabit Ethernet LANs are widely installed in enterprises, Intranet bandwidth has grown quickly. With active adoption of ADSL and cable modems, broadband accesses in the SOHO and residential markets, more data traffic is generated in these markets as well. Presently, most telecom carriers use SONET/SDH equipment to “aggregate” data traffic in the MAN network (Metropolitan Area Network) before accessing the Internet backbone network. Because of the intrinsic limitations of SONET/SDH equipment in transporting data traffic, especially in terms of bandwidth scalability and provisioning efficiency, there is a need to find a broadband access solution that can overcome the drawbacks of SONET/SDH. Because the inherent simplicity of the technology, Ethernet offers cost-effectiveness, ease of networking, a packet-based IP friendly protocol, and rapid provisioning advantages while competing with other networking technologies. These advantages, coupled with the newly developed Gigabit WAN capability have positioned Gigabit Ethernet as a compelling technology to break the bandwidth bottleneck in the MAN environment. We review the enhancement of Gigabit Ethernet technology and discuss the pros and cons of using Gigabit Ethernet technology in the MAN network. We also address the implications of this technology evolution on telecom carriers. Fuzzy Multi-Criteria Decision Making methodology was used to evaluate Gigabit Ethernet and SONET/SDH MAN access strategies. The survey results show that the SONET/SDH MAN access strategy received a higher utility score in satisfying the multi-objectives than the Gigabit Ethernet access strategy. Finally, although global telecom deregulation has sparked competition for long distance, international, and cellular service, there remains a lack of competition in the local loop environment. This may be of particular concern in the Internet broadband service era due to the potential aggregation of service providers. In order to foster local loop competition, special government policy attention and regulation is required. We analyzed various emerging access technologies and policy approaches. Based on the analysis, fiber offers the best bandwidth capacity while WLAN and WiMAX provide good mobile broadband access capability for end users. From a policy perspective, if a majority of the CLECs (Competitive Local Exchange Carriers) are unable to effectively compete with incumbent carriers, then a CLEC consolidation - leading to a well-controlled monopoly - could be a solid option for future local loop networks.