分散式設計之多重網域控制器

Abstract

軟體定義網路 (SDN) 已建立一個新的網路基礎，能夠解決許多現有網路的難題與限制。近幾年來，軟體定義網路深獲業界與學術界歡迎，將基礎網路架構改為軟體定義網路之後，在這緊密整合的領域，開創了許多新研究議題。軟體定義網路將要在異質網路與廣域網路上實現，包括資料中心、行動網路、企業網路等等需要強健穩定且能延展擴充的控制平台。

本論文提出一個透過分散式設計的多網域控制器，足以處理廣域網路的使用需求，並維護各個網域的隱私。此外，本控制器也能處理跨網域連線失能的問題，能夠自動設置替代路徑。控制器之間所傳遞的訊息，其傳輸量僅僅只有足以維繫端點與端點間服務。而控制器之間傳遞訊息的方式，是透過 RabbitMQ 建立的極輕量的控制頻道，因此控制器間的通訊虛耗得以控制在較低的程度。而各網域控制器所需要儲存的資訊都放置在各網域本地端的資料庫中，而依據不同模組的需求，取出或新增資料。本多網域控制器是基於RYU控制平台之上，且是截至目前我們所知的RYU 平台上的第一個分散式的應用程式。

Software-Defined Networking (SDN) has set up the base of a new networking infrastructure to solve many of current obstacles and limitations which current networks have. Within few years SDN has gained popularity in the industry and academia. Change in networking infrastructure in the form of SDN has opened up the research areas in this tightly integrated field. Software Defined Networks (SDN) enabled multi-domain networks are core of heterogeneous and wide area networks. The SDN technology is going to be implemented in datacenter networks, mobile networks and enterprise networks. Such networks are demanding and requires independent and private control plane and thus these networks much be resilient, scalable and expandable.

In this thesis DMC, a Distributed approach in Multi domain Controllers that is able to cope wide area networks while preserving the privacy of their domains. It also deals with the link failure across the domains making it resilient in terms of link failure. Controller manages their own network domain and exchanges only necessary information with other controllers to entertain end to end services. East West interface is defined between the controllers that is achieved by a very light weight control channel and is using RabbitMQ as its messaging model. It also helps to reduce the extra overhead since only necessary information is exchanged between the domains. That information is stored in the centralized database present in each domain where other modules retrieve/enrich information from database according to their requirement. Our application is implemented on top of RYU control platform and to best of our knowledge this is the first distributed application designed on RYU control platform.