Eucalyptus is a software platform for the implementation of private cloud computing on computer clusters. There are enterprise edition and open-source edition. Currently, it exports a user-facing interface that is compatible with the Amazon EC2 and S3 services but the platform is modularized so that it can support a set of different interfaces simultaneously. The development of Eucalyptus software is sponsored by Eucalyptus Systems, a venture-backed start-up . Eucalyptus works with most currently available Linux distributions including UbuntuRed Hat Enterprise Linux (RHEL)CentOSSUSE Linux Enterprise Server (SLES), OpenSUSEDebian and Fedora. Similarly Eucalyptus can use a variety of virtualization technologies including VMwareXen and KVMhypervisors to implement the cloud abstractions it supports. Eucalyptus is an acronym for “Elastic Utility Computing Architecture for Linking Your Programs To Useful Systems”.