Contrail component	What this component does	What you need before you can install it	How it fits in Contrail	Can be used independently from Contrail
Contrail PaaS (ConPaaS)	Platform-as-a-Service for web applications (Java, PHP), NoSQL, SQL, Task Farming, MapReduce.	Access to Amazon EC2 or a working OpenNebula Cloud.	"Builds on XtreemFS to store data and applications. Interfaces with the federation layer."	yes.
Contrail XtreemFS	Highly available cloud file system with policy-based customization e.g., to control the placement of data.	File system clients are available for Linux, MacOSX and Windows. Can also be used in Hadoop or directly through client libraries for Java and C++.	Can be used as a component at several levels, PaaS and IaaS, where reliable storage is needed.	yes.
Contrail Security	Federated support for identity management. Security for SLA support.		Provides federated identity management for users and resources providers. Provides security at all levels of the federation.	Perhaps, but it needs a federation to be useful.
Contrail SLA	Definition of SLA's at federation level. Splitting SLA's to resource providers. Monitoring of SLA's.	Cloud federation.	Provides SLA definition, monitoring and enforcement at all levels of the federated Cloud.	Perhaps. But it would need adoption. It could be used by a Cloud provider to manage the SLAs. It should not need the federation.
Contrail VEP	Virtualized Execution platform.	IaaS infrastructure with resource providers using OpenNebula or other supported Cloud.	Virtualizes resource providers at the IaaS level and presents them to the PaaS level.	VEP can work as a standalone component.
Contrail VIN	Virtualized Infrastructure Network.	IaaS infrastructure with resource providers using OpenNebula or other supported Cloud.	It integrates (federated) IaaS resources of an application by providing a virtual private network.	VIN could be integrated in other Cloud solutions.
Contrail Federation	Integrates all components of Contrail into a single federated Cloud.	Cloud providers.	Turns a number of individual Clouds from resource providers into a single Cloud. Allows users to execute services on this federated Cloud.	Federation is a core Contrail service, that can be used as a separate component by relying on SLA technology and the availability of suitable Cloud providers.