The recent trend in cloud computing brings additional security risks. Cloud computing involves the use of internet-based data storage and computing resources.
Rather than using computer resources located within an organisation, the organisation accesses shared resources which are owned and run by a third-party data centre. This enables organisations to react faster and be more flexible, with the ability to fairly rapidly increase their computing resources when demand is high and also reduce them when demand drops. This is something that cannot easily be achieved with in-house computing resources, which usually involve investing in hardware.
Organisations may also set up their own cloud systems to provide more flexilble access to in house applications and data.
Cloud computing has its own security issues, Some argue that using cloud computing may improve the security of data because a large third party data centre is able to devote greater resources to security than an individual company can. However, because these large data centres hold large amounts of data from many different clients on their systems, they become attractive targets for cybercriminals.
Organisations that store their data on the cloud no longer have physical access to the servers and discs on which their sensitive data is stored. This data is instead exposed to internal attacks from within the third-party company that hosts the data. The hosting company must take extra precautions to protect against internal attacks.
The data held for one organisation by a cloud computing hosting company may also share the servers and disc drives with data held for other organisations, so the hosting company must ensure that each client's data is properly isolated from other clients'.
The server computers in data centres are often virtualised (known as server virtualisation), with one physical computer running a number of different virtual machines for clients. The virtualisation software adds an additional layer of complexity to the system and creates the possibility that vulnerabillties may exist in the virtualisation software.
It is very common for server computers to use virtualisation software that allows one large and powerful server computer to operate as if it were several smaller systems carrying out specific functions. In cloud computing, this allows a data centre to provide a customer with what appears to be their own dedicated server computer. In reality, it is just one is many different virtualised servers running on a large single virtualised server.