Quoting from the Stratus official announcement:
Stratus Technologies, Inc., a leader in IT technology and services for continuous availability, and XenSource, Inc., the leader in infrastructure virtualization solutions based on the open source Xen™ hypervisor, today announced they have signed a collaborative agreement with the goal of fusing continuous availability and virtualization technologies to create new IT infrastructure solutions with superior reliability, flexibility and manageability.
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Under terms of the non-exclusive agreement, Stratus will work with XenSource to include XenEnterprise as an integral component in Stratus’ Continuous Processing architecture…