以 Web 為基礎探討多廠商環境下的 SNMP 網路管理

Abstract

論文內容主要探討並解決多廠商 SNMP 網路管理環境的網管問題，其中包含 (一) 管理平臺上存在若干功能相似的 SNMP Manager、 (二)網路管理平臺集中在少 數高階工作站中。針對上述造成管理成本高漲與管理效能降低的情況，我們的研 究動機如下(一)降低網管成本 (Management Cost)、(二)提高網管應用程式的效率與 彈性 (Management Efficiency and Flexiblity)、 (三)與現行通訊協定及管理協定標準 相容。基於 WWW 的普遍性與一致性原則，將 Web Technology 套用到 SNMP網路 管理環境能讓 SNMP 網管系統適用的範圍更普遍、管理的方式更一致化。 研究目標希望以 Web Browser 為新一代網管應用程式並擴大管理範圍，網路 管理者使用 Web Browser 存取網路上任何可用的 SNMP Agent。網管普遍化與一致 化是降低網管成本與提高網管效率的主因，因此維持 Web Browser 與 SNMP Agent 的一般性為我們主要的研究動機之一。在實際設計階段我們將 SNMP Manager 與 Web Server 整合在一個稱為 Proxy Agent 的獨立模組中，因此 Web-Based SNMP 網 管系統的架構為包含 Web Browser、Proxy Agent 與 SNMP Agent 之三層架構 (Three- Tier)。 Proxy Agent 內部採用 IPC 方式來解決 SNMP 與 HTTP 兩者無法直接聯繫的 問題。SNMP Manager模組包含：整體資料設定、搜尋遠端網路管理設備上的所有 SNMP Agent、取得遠端網管設備資訊以及處理 SNMP 訊息等四個功能。我們以 SNMP 為出發並引入 Web Technology 作為驗證想法的基礎，說明網管系統整合此 兩種協定將能獲得事半功倍的效果。

We focus on solving the following existing problems of SNMP network management in multiple vendor environment. First, a management station may have some SNMP Managers and each of them has similar or duplicate management functions. Second, the SNMP management stations are centralized at some workstations. These problems result in high management cost and low performance. We consider some management factors. First, reducing the duplicate management functions will save much management cost and gain more efficient and flexible. Second, Keeping compatibility to the original management standard is more important. Thus, we present an approach that applies the Web technology to the SNMP environment and solve the above SNMP problems. In accordance to the current trend, we think the popular Web browser is suitable for the new generation management application. Network managers use Web browser to access SNMP information from any available SNMP agent. In order to keep the well-defined properties of both Web browser and SNMP agent, we do not modify the pre-defined properities of them. We integrate both Web Server and SNMP Manager into a Proxy Agent and the Web-Based SNMP network management system is a three-tier architecture. It consists of Web browser, Proxy Agent, and SNMP Agent. The only thing we need to do is Proxy Agent design. It is cheaper and flexible to extend the existing SNMP management scopes. Network managers monitor and control the remote network devices through the Proxy Agent. Our approach shows how to coordinate the UDP and HTTP protocols. The internal communication of Proxy Agent are two IPC mechanisms and they are Message Passing and File Sharing. There are four major functions in SNMP Manager module and they are Global Initializations, Remote agents discovery, Remote agents information polling, and SNMP message processing. We have achieved our goals and illustrated how to take advantages of the above two protocols and finally gain better benefit.