Abstract: Over the last few years, many open source Cloud Management Platforms (CMPs) have come into existence. Developers, Cloud Providers and Consumers need to resolute to a cloud platform which best suits their needs. OpenNebula, CloudStack, Eucalyptus and OpenStack are among the major players that commercially provide a cloud management platform. Having several options to choose from, it can become diffcult for new businesses to select a platform which caters to all their needs. However, the market has room for several open source cloud platforms that perform different tasks and fnally ft together into an extensive cloud ecosystem. Some existing literatures only compare the basic features of these platforms. The main goal of this paper is to provide a practical reference to help businesses understand the features being provided by the above-mentioned Cloud Management Platforms and assist them in making a selection of a CMP that best suits their requirements. All of these platforms provide Infrastructure as a Service. Keywords: Cloud Management Platform (CMP), CloudStack, Eucalyptus, OpenNebula, OpenStack. Comparative Study of OpenNebula, CloudStack, Eucalyptus and OpenStack P. Bedi 1* , B. Deep 2* , P. Kumar 3 , and P. Sarna 4 1 Department of Computer Science, University of Delhi, New Delhi, India. Email: pbedi@cs.du.ac.in 2 Department of Computer Science Bhaskaracharya College of Applied Sciences, University of Delhi, New Delhi, India. Email: bhavya.deep@bcas.du.ac.in 3 Department of Computer Science Bhaskaracharya College of Applied Sciences, University of Delhi, New Delhi, India. Email: par4parveen@gmail.com 4 Student, B.Tech Computer Science, Bhaskaracharya College of Applied Sciences, University of Delhi, New Delhi, India. Email: prateeksarna95@gmail.com *Corresponding Author I. IntroductIon Cloud Computing provides on demand sharing of computing resources over the internet instead of using local servers to manage software programs. [1] Cloud computing provides three types of services: (a) Software as a Service (SaaS) (b) Platform as a Service (PaaS) (c) Infrastructure as a Service (IaaS) Software as a service comprises of web applications which work on remotely located systems that are maintained by other organizations and connect to users’ systems through the internet. SaaS enables users to sign up and instantly start using business applications. The data and applications are readily accessible from any connected computer. If a computer malfunctions, there is no loss of data as the data is preserved in the cloud. With the help of SaaS, users are saved from buying, installing, and maintaining their software. Platform as a service makes available a cloud-based environment providing users with all the resources to build and deploy cloud applications without the complications of purchasing and maintaining their hardware and software as well as hosting services. PaaS enables developers to develop applications and market them in a fast and easy way. Web applications can be distributed to both private and public cloud with ease. Infrastructure as a service provides organizations with computing resources such as storage devices, servers, networking and data centers on pay for use basis. IaaS enables companies to provide fexible and on demand services. Companies also beneft as there is no need for them to invest in their own hardware. [2] This paper primarily focuses on IaaS cloud platform. A. Open Source Cloud Management Platforms i. OpenNebula OpenNebula provides simple but effective and customizable solutions for extensive management of virtualized data centers to permit public, private and hybrid IaaS clouds. OpenNebula provides fexible architecture, networks and modules which are easy to integrate into any data center. It also supports Xen, VMware, KVM and can make use of Amazon EC2s. OpenNebula consists of the following components: Front-end, Hosts, Datastores and Physical Networks as shown in Fig. 1. International Journal of Distributed and Cloud Computing 6 (1) June 2018 37-42 http://www.publishingindia.com/ijdcc