免付費服務電話是為許多公司、服務機構或政府機構 …等會提供給顧客撥打的專線，其一特色為受話方付費，因此撥打方不需要支付任何的通話費用，因此顧客在尋求服務協助時，撥打的意願也會有所提高，對免付費服務電話提供者的服務印象有所提高。
此外，在申請中華電信之0800免付費電話時，必須提供相關證明文件以及填寫申請書，開通時間約在三個工作天內，申請流程較為繁雜與需要時間等待。此外，大部分的免付費電話使用者為機構或者公司，我們希望讓個人服務提供者也能夠更方便的擁有個人的免付費電話服務。有鑒於此，我們設計出一個更具有效率與彈性的方式，讓需要申請免付費電話的個人服務提供者(例如：業務人員)…等，能夠更快速地、方便地建立屬於自己的免付費服務專線。
因智慧型手機已相當普及，我們決定將此應用開發於兩大手機系統Android 與iOS，並且使用Cloud Server將HTTP請求發送至由Asterisk所架設的SIP(Session Initiation Protocol) Server，並將兩通於PSTN(Public Switched Telephone Network)上的電話透過Asterisk所提供的函式將之橋接起來，達到雙方能夠通話的目的，並藉由程式實作單方面支費的功能，達到類似0800免付費電話的效果。此外，由於服務提供者通常會有名片來展示自己的身份，為了讓服務提供者能夠更方便的提供自己的免付費專線，我們嵌入網址的 QR Code 置於手機應用的電子名片中，並提供分享與掃描 QR Code功能。我們實作了免下載手機應用即可快速擁有免付費通話捷徑的建立方法，讓客戶能夠快速地使用免付費專線。
在此篇論文中，將先對此想法透過一個的問卷做評估，並且介紹此系統的三大核心：RESTful API web service、App以及響應式網站是如何設計與實作，在論文的最後將對此系統做結論以及未來可增進之處。

There are companies and organizations providing customer service by means 080 toll-free phone. The special characteristic differing from the normal phone number is that the callers do not need to pay any calling fee, the calling fee was paid to the telecommunications by the callee. Consequently, the willingness to call to the service provider will be improved when the customers have questions to be solved. Also, Providing the toll-free phone helps the service provider a make good impression on customers.
As people are required to provide the documents, id card to telecom service provider if they would like to apply for a toll-free phone. It takes about three days to activate the service. It is time-needed. Besides, we hope to make the toll-free phone more accessible to the personal service providers. Based on the above motivations, we design a more efficient system helping personal service provider building the toll-free phone service more easily and conveniently.
Due to the growing popularity of smart phone devices, we decided to develop mobile applications on both Android and iOS. The application uses the cloud server to send HTTP requests to the Asterisk-based SIP (Session Initiation Protocol) server to bridge two phone calls on PSTN (Public Switched Telephone Network). By this approach, we can bridge two separated phone calls and make people communicate. The charging system is also implemented in our web service so that we can decide whom to be charged based on the calling time.
In this thesis, we will evaluate the feasibility by a survey and describe how we implement this system including application, web service and the responsive website. At the end, I will make a conclusion about this system and discuss the future works.

[1] 中華電信. 0800受話方付費電話申請說明. [Online]. Available: http://www.cht.com.tw/enterprise/rp-0800-apply.html
[2] Digium, Inc. Asterisk. [Online]. Available: http://www.asterisk.org/
[3] Network Working Group. (2002) RFC 3261 - Session Initiation Protocol. [Online]. Available: https://tools.ietf.org/html/rfc3261
[4] Wikipedia. Public switched telephone network. [Online]. Available: https://en.wikipedia.org/wiki/Public_switched_telephone_network
[5] Google. Material design. [Online]. Available: https://www.google.com/design/spec/material-design/introduction.html
[6] Github. Github Flow. [Online]. Available: https://guides.github.com/introduction/flow/
[7] Naver. LINE. [Online]. Available: http://line.me/zh-hant/
[8] Facebook. Facebook. [Online]. Available: facebook.com
[9] Facebook. Facebook Messenger. [Online]. Available: https://en.wikipedia.org/wiki/Facebook_Messenger
[10] Facebook. (2016, April) Say Hello to Messenger Codes. [Online]. Available: https://www.facebook.com/messenger/posts/930151277104553
[11] Apple. Apple Push Notification Service. [Online]. Available: http://apple.co/1iP08v6
[12] Apache Foundation. Tomcat. [Online]. Available: http://tomcat.apache.org
[13] Roy Thomas Fielding, "Architectural Styles and the Design of Network-based Software Architectures," Information and Computer Science, University of California, Irvine, PhD Dissertation 2000.
[14] Wikipedia. Representational State Transfer. [Online]. Available: https://en.wikipedia.org/wiki/Representational_state_transfer
[15] The Internet Society. (1999) Hypertext Transfer Protocol -- HTTP/1.1. [Online]. Available: https://tools.ietf.org/html/rfc2616#section-9
[16] Oracle. Jersey. [Online]. Available: https://jersey.java.net/
[17] Wikipedia. NoSQL. [Online]. Available: https://en.wikipedia.org/wiki/NoSQL
[18] MongoDB Inc. MongoDB. [Online]. Available: https://www.mongodb.com/
[19] ObjectLabs Corporation. mlab. [Online]. Available: https://mlab.com
[20] Node.js Foundation. node.js. [Online]. Available: https://nodejs.org/en/
[21] Wikipedia. Responsive web design. [Online]. Available: https://en.wikipedia.org/wiki/Responsive_web_design
[22] W3C. CSS Specification. [Online]. Available: http://www.w3.org/Style/CSS/specs.en.html
[23] Google. Material Design Lite. [Online]. Available: https://getmdl.io
[24] Heroku. Heroku. [Online]. Available: https://www.heroku.com
[25] Amazon. AWS Elastic Beanstalk. [Online]. Available: https://aws.amazon.com/elasticbeanstalk/
[26] Amazon. Amazon S3. [Online]. Available: https://aws.amazon.com/tw/s3/pricing/
[27] Google. Google App Engine. [Online]. Available: https://cloud.google.com/appengine/
[28] Wei-Tsung Lin, "Design and Implementation of Cloud Bridging Switch Based Conference System on Android Platform," Departmentof Computer Science, National Tsing Hua University, Hsinchu, Taiwan, Master thesis 2014.
[29] Wikipedia. Universally unique identifier (UUID). [Online]. Available: https://en.wikipedia.org/wiki/Universally_unique_identifier
[30] Auth0. JSON Web Tokens. [Online]. Available: https://jwt.io
[31] RestApiTutorial.com. Resource Naming. [Online]. Available: http://www.restapitutorial.com/lessons/restfulresourcenaming.html
[32] Trygve Reenskaug, "The original MVC reports," Dept. of Informatics, University of Oslo, Oslo, Report 2007. [Online]. Available: http://heim.ifi.uio.no/~trygver/2007/MVC_Originals.pdf
[33] Cocoapods. Cocoapods. [Online]. Available: https://cocoapods.org
[34] Google. libphonenumber. [Online]. Available: https://github.com/googlei18n/libphonenumber
[35] W3C. (2014, Oct.) HTML5 specification. [Online]. Available: http://www.w3.org/TR/html5/
[36] Jeremy Ashkenas. Backbone.js. [Online]. Available: http://backbonejs.org
[37] Wikipedia. User agent. [Online]. Available: https://en.wikipedia.org/wiki/User_agent
[38] Google. Progressive web apps. [Online]. Available: https://developers.google.com/web/progressive-web-apps/
[39] W3C. (2015, June) Service worker. [Online]. Available: https://www.w3.org/TR/service-workers/