Xen / XCP / XAPI Overview

NOTE: XCP is deprecated. It was the open source equivalent to XenServer, but now XenServer is open source as well. People interested in XCP should be exploring the open source XenServer instead, as XCP is no longer updated. For Xenserver, go to xenserver.org.

This table gives a high level overview of the different high-level features of Xen, XCP and XCP-XAPI packages in Linux (Debian & Ubuntu) (also see Project Zeus (for Fedora)).

Description	Xen	XCP	XCP-XAPI packages in Linux
Hypervisor	latest	lagging	as in latest Linux distro
Dom0 OS	See Dom0_Kernels_for_Xen	CentOS (5.7 in XCP 1.6)	See Debian, Ubuntu and Fedora
Dom0	32 and 64 bits	32 bits	32 and 64 bits
Linux 3 PVOPS Dom0	Yes	No	Yes
Toolstack	XM (deprecated), XL, libvirt	XAPI with XE	Same as XCP
Features	Xen Feature List	Xen Feature List and XCP Feature List	Xen Feature List and XCP Feature List
Storage, Network, Drivers	Build and get yourself	Integrated with Open vSwitch, multiple storage types & drivers	Get them yourself (only core components are provided)
Configurations	Everything	Constrained by XAPI	Same as XCP
Usage Model	Do it yourself	Shrink wrapped and tested	Do it yourself
Distribution	Source code or via host Linux or Unix distributions	Delivered as ISO on xen.org	Via host Linux or Unix distributions

Also see some interesting videos on the subject.