Last week Amazon announced it's new cloud computing service - The Amazon’s Elastic Block Store (EBS) . It's a remote storage service, with excellent storage/cost ratio which is even advertised as replacement for large storage systems of the enterprise. Naturally, the ever controversy seeking journalists hurried to declare time of death to the enterprise data center and included this view:
Though most businesses are quite comfortable in using external utility
services for electricity, water, and Internet access — and we even use banks to
hold and pool our money with others “off site” — we are still largely unready to
move computing off-premises, no matter what the advantages
It is correct that certain elements are used as external utilities, but let's compare services from a realistic point of view
- Electricity as a service - because everyone is entirely dependent on electricity, the grid itself is designed to be resilient, have fast fail over time, survive major catastrophic events at power plants or within the grid, and even re-route additional supplies from other countries if need be, at horrible costs but it does work! Oh, and for the simple case of a grid glitch, we'll spend a $500 on a UPS and another $5000 on a diesel generator and we're all set!
- Data storage as a service - For data storage services, information is needed here and now - exactly like electricity. If we are to outsource our cloud information storage to a provider, that may be well and good as long as it works. However in the information security world, there are three key concepts. Our cloud data storage must guarantee commensurate levels of
- Confidentiality - in cloud computing location is an ambiguous concept. So data will exist on different storage elements, at different physical locations, will traverse millions of miles of physical networks not related to or in any way responsible to the customer, as long as it's there. Who will guarantee that confidentiality is maintained? Oh, and I forgot - you ACCESS the data via the Internet. Whenever a confidentiality breach does occur it can always be blamed on your Internet connectivity and breach of security at the access provider, not the storage service provider
- Integrity - will probably be maintained, since there are very simple ways of doing comparison and keeping a small subset of control information with each set of data - as long as fragments don't get lost, in which case we have a problem of...
- Availability - in cloud computing information is everywhere, and gets collected and presented at the user's request. If for any reason this data cannot be reconstructed and verified it is lost. And again, the access to the information is through the Internet - which is not service with guaranteed availability, since it depends on international mesh network controlled by a multitude of independent entities. Unless you spend top dollar on dedicated data links nobody will sign a strong SLA for Internet access - it's impossible to achieve.
But why don't we have a local backup, just like the UPS? Of course we can, it's known as an enterprise data center!
While there are strides made in the right direction of cloud computing it's current level of usability is restricted by the "best effort" concept of the entire network on all sides. So the users of cloud computing are the ones that find it acceptable to:
- have delays in access to information
- have some data lost and
- information leakage will not make a significant impact.
In the meantime, the enterprise data centers are still humming strong
Talkback and comments are most welcome