Developers of the Xen open source hypervisor are trying to make Xen the industry's cloud-building platform of choice with a new initiative designed to expand upon the hypervisor's ability to create "secure, customizable, multi-tenant cloud services."
The Xen Cloud Platform, announced Monday at VMworld in San Francisco, is also an attempt to provide compatibility among different types of virtual machines and cloud services. Any virtual machine, whether it's created by VMware, Citrix or another vendor, should be able to run on cloud services using the expanded Xen platform, says Simon Crosby, the CTO of Citrix's virtualization division. Customers should be able to easily move workloads from internal networks to external cloud services without worrying about what type of hypervisor is being used, he says.
"We firmly believe, as a group of vendors, that [something is wrong] if the cloud market evolves in a way that requires the enterprise to ask the cloud vendor whose virtual infrastructure product was used to build the cloud," Crosby says.
Citrix, which sells a commercial version of the Xen hypervisor called XenServer, is the host of Xen.org, home of the open source project and the Xen Cloud Platform initiative. Citrix will contribute to and draw from technology in the Xen cloud initiative, which also has support from vendors including AMD, Dell, Eucalyptus Systems, Fujitsu, HP, GoGrid, Juniper, NetApp, Novell, and Oracle. Numerous cloud platforms are already using the Xen hypervisor to deliver computing services to enterprises, such as Amazon and Rackspace.
Xen.org will attempt to achieve broad interoperability across virtualization platforms with standards such as the Open Virtualization Format, allowing "virtual appliances ... packaged in a hypervisor-independent format for easy transport between internal and external clouds with no vendor lock-in," according to the announcement.
The first release of the Xen Cloud Platform is on track for Q4 2009, says Ian Pratt, creator of Xen and founder of Xen.org. The cloud platform will go beyond today's Xen hypervisor with features such as virtual switches to enable multi-tenant networking, and storage management tools to stitch local disks together for improved flexibility and high availability, he says.
The virtual switch will help cloud providers build "sophisticated network service offerings, including per-tenant network management, intrusion detection, firewalling, routing, and load balancing," according to the Xen.org announcement. Meanwhile, expanded storage features will "enable virtual machines and their physical storage to be widely separated without disrupting application performance."
The Citrix and Xen.org announcement is reminiscent of VMware's decision to call its virtualization platform a "cloud operating system." But VMware's attempts at interoperability involve only its own hypervisor and cloud platform providers who have partnered with VMware and use the company's vSphere software.
Vendors collaborating on Xen Cloud Platform have essentially agreed to distribute a common platform, whereas historically individual Xen vendors have tried to claim their version of Xen is better than others, Crosby says. "It should unify the vendors to a greater extent," he says.
"The Xen Cloud Platform raises the bar -- going beyond the hypervisor to deliver a complete run-time virtual infrastructure platform product that virtualizes storage, server and network resources," Enterprise Strategy Group analyst Mark Bowker says in a press release. "This announcement aligns the Xen community around a common compatible product, increasing the opportunity for value-added offerings from all ISVs, while promising to run VMs from any hypervisor."