One of the issues currently holding back the adoption of cloud computing is the difficulty of moving data between different services. The problem stems from the fact that cloud providers and virtualisation companies work with their own competing proprietary technology stacks, meaning tasks such as moving data held by a cloud computing vendor to an internal private cloud can be a tricky affair. Virtualisation company Citrix is attempting to tackle this problem with its OpenCloud technology, unveiled at its Synergy user and partner conference in Berlin recently.