The Research On Dynamic Evolution Methods Of SaaS Software Based On Cloud Monitor Mechanism

With the continuous development of cloud computing,there have been a software model which is different from the traditional.SaaS software not only changed the business model of traditional software,but also changed the way people use the software.SaaS software requires service providers to provide services for users whenever and wherever needed.The static evolution mode in downtime will affect users and cause service providers to suffer economic losses.Therefore,SaaS software's need for dynamic evolution is particularly urgent.The purpose of the text is to propose a dynamic evolution method of SaaS software based on the cloud monitor mechanism.First,it summarizes the current research background status and introduces the related work of this paper.Then based on SaaS software configurable,multi-tenant and scalable features,the SaaS software structure model,SaaS software metamodel,is proposed.It supports the SaaS software maturity model and can model any maturity level SaaS software.The SaaS software metamodel is divided into multiple layers:application layer,software instance layer,tenant layer,presentation layer,cloud monitor layer,and service entity layer.In this paper,the SaaS software metamodel is formally defined,and the representation of each maturity level is discussed.Afterwards,using the SaaS software metamodel as a view,the dynamic evolution method of cloud monitor mechanism is proposed.Because the cloud monitor layer is the implementation and execution layer of SaaS software functions,the dynamic evolution of SaaS software is targeted at the cloud monitor layer.Cloud Monitor is a special service that provides universal support for SaaS software and guarantees the dynamic evolution and correct implementation.This part first defines the structure and function of cloud monitor,and then formulates evolution rules according to different evolutionary stages.The dynamic evolution process of the cloud monitor mechanism is similar to the process switching in the operating system.It uses the protection field and jump method to exchange the logical continuity of the execution process.Then according to the different structures of the basic Petri net structure cloud service network in the cloud monitor layer,a dynamic evolution algorithm suitable for different structures is proposed.The order structure includes the addition,deletion,and replacement operation algorithms of the service,and it is the basis of all other structures.In the selection structure,bifurcation places and confluence places are proposed,and the evolution of the two special structures is discussed.The implementation of concurrent structural evolution is similar to that of the first two structures.Finally,the author of this paper developed and implemented CloudMonitor,a tool that supports the cloud monitor mechanism.It can dynamically evolve the cloud service network of SaaS software.Take a CRM system as an example for case analysis.Firstly,this structure model of CRM is established.Then,according to several evolution requirements,CloudMonitor tool is used to perform dynamic evolution of cloud service network that needs evolution,and the execution result is analyzed to verify the feasibility of this method.