Two virtualization software startups will vie for the spotlight at the LinuxWorld conference in Boston next week with competing offerings based on the open-source Xen hypervisor.Startup XenSource, which also manages the development of the open-source hypervisor, will launch a commercial virtualization platform, XenEnterprise, based on the latest version of the hypervisor.Red Hat and Novell are both integrating the open-source Xen hypervisor technology into the next versions of their Linux operating systems, Red Hat Enterprise Linux 5 and Novell Suse Linux Enterprise Server 10, shipping this year.XenSource says that its product will allow users to virtualize Linux workloads as well as workloads on other operating systems, including Windows.But for XenSource to work properly with Windows, with older versions of Red Hat and Suse distributions and other operating systems, XenSource is relying on hardware virtualization capabilities Intel and Advanced Micro Devices (AMD) are building into their next-generation chips. That means customers will have to buy new hardware to take full advantage of XenSource in a heterogenous OS environment, said analysts."Certainly, the fact that you need to be using brand-new hardware is a selling disadvantage out the door," said Gordon Haff, senior analyst for Illuminata in Nashua, N.H."Realistically, hardware-based virtualization support is not going to be ready for prime time until 2007," said Tony Iams, senior analyst at Ideas International in Rye Brook, N.Y.XenEnterprise is currently in beta and will be generally available around June or July, said officials. Pricing has not yet been determined.Also at the show, data-center virtualization and management startup Virtual Iron Software will launch the next iteration of its virtualization software, which will also be based on the open-source Xen hypervisor. Virtual Iron previously used its own hypervisor. The new release will also include Virtual Iron\u2019s policy-based management capabilities.Virtual Iron is also banking on the virtualization technologies in next-generation AMD and Intel chips to enable users to virtualize multiple OS workloads.Beta versions of Virtual Iron 3 for Xen Enterprise Edition will be available in July for Linux and September for Windows, according to Virtual Iron. Pricing for Enterprise Edition will start at US$1,500 per server. Virtual Iron said it will also offer a free single-server version and community developer version as downloads from its website.Analysts also questioned whether Xen is ready for prime time."This is still relatively early days for Xen, it certainly doesn\u2019t have the level of maturity and time in market that VMware has had," Haff said. "And I certainly wonder if there is enough money to support two companies doing this out there." Veteran virtualization vendor VMware meanwhile will announce at the show that it is providing its virtual machine disk format specification free to developers and vendors. Altiris, BMC, IBM, Symantec and Trend Micro are some of the software companies that have already used the specification to develop add-on technologies, and VMware hopes to spur more development by opening up its specification.-Shelley Solheim, IDG News ServiceCheck out our CIO News Alerts and Tech Informer pages for more updated news coverage.