中小企業的VoIP整合於傳統按鍵電話系統應用之研究與實作

Study of VoIP Integrated with the Traditional Key Telephone System for Small and Medium Enterprise Applications

呂志輝(Chih-Hui Lu)

指導教授 ： 賴柏洲

國立臺北科技大學/電資學院/電子電腦與通訊產業研發碩士專班/碩士(2009年)

https://doi.org/10.6841/NTUT.2009.00023

摘要

在過去，傳統的電信網路(Public Switched Telephone Network；PSTN)與網際網路(Internet)分屬不同通訊網路，電信網路僅單純的用來傳輸類比語音及傳真，而網際網路則是處理數位文字、資料的傳送。由於不斷更新的數位信號處理能力，結合網際網路與電話多功能技術，衍生出新的應用與產品服務，網際網路語音協定(Voice over Internet Protocol；VoIP)應用也越來越廣泛，透過網路傳送語音、檔案、影像、文字…等訊號，不僅打破傳統電信市內、長途、國際電話收費標準，並隨著傳統電話與行動電話的技術發展，VoIP更能提供多元化的加值服務。
事實上，VoIP的應用和服務行之有年，中小企業建置率卻偏低，其主要原因在多數人的思維一直著重在節省通訊費的成本方向，而忽略了如何在現今的高速網路架構下及企業內相關的通訊設備上，有效的規劃利用來建置一套具體且節省相關設備投資費及話費的可行方案，利用方便性、經濟且有效的整合手段，真正達到增加企業通訊效率及節費的目的。
本論文主要研究VoIP的語音技術相關內容及與傳統的按鍵電話系統(Key Telephone Systems；KTS) 設備介接技術，透過會議初始協議（Session Internet Protocol；SIP）代理伺服器及VoIP閘道器（Gateway）結合PSTN網路，設計、製作一個企業內網路電話（IP Phone）的嶄新系統實例，本論文結果的貢獻能使中小企業及家庭、個人用戶皆可享受到無限免費網路通訊的方便性，同時可降低企業系統建置費用及通話費用，並享受各式各樣的電信加值服務。

關鍵字

電信網路 ； 網際網路語音協定 ； 按鍵電話系統 ； 會議初始協議 ； 閘道器

並列摘要

In the past, a traditional Public Switched Telephone Network （PSTN） and the Internet are two individual communication networks, where PSTN is purely used for analog voice calls and fax while the Internet network deals with those digital information. The advancement of digital signal processing technologies combined with the Internet and telephone functionalities, has resulted in newer applications and services. Voice over Internet Protocol（VoIP）applications have enabled different uses including voice, data, images, and text etc. over Internet. Not only the bill of city, long distance and international call in the traditional telephone model can be eliminated, more diverse services through the extension of traditional and mobile phone facilities are provided.
VoIP applications and services have been on the market for several years, but the adoption rate in medium-to-small enterprises was commonly lower than expected. The main factor is in antiquated thinking where communication costs often received fewer budgets, and neglected the fact that corporate communications should be built on the high-speed network infrastructure. An effective solution to establish the practical and cost effective communication system is a necessity in today’s corporate management – where the convenience and economical integration models can truly target the enterprise cost saving and unlimited free calls.
In this thesis, we focus on integrated technology between VoIP equipments and traditional Key Telephone Systems（KTS）and are to organize a real world case study by integrating Session Internet Protocol（SIP） proxy server and VoIP Gateway to the PSTN network. A new IP Phone system for internal communications is designed and implemented in a corporate environment. The results of this thesis may benefit the small and medium enterprises, ordinary home offices, and individual users access to the convenience of unlimited and free VoIP communication. At the same time, it may help lower the cost of enterprise system infrastructure and calling fees, in addition to the diverse telecommunication services that comes with the technology.

並列關鍵字

PSTN ； VoIP ； KTS ； SIP ； Gateway

參考文獻

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[8]RFC 1889 - A Transport Protocol for Real-Time Applications

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