To Grasp the Cloud—Fundamental Concepts - Deploying and Managing a Cloud Infrastructure - page 30

up new virtual servers whenever needed and spin them down when demand goes down.
Compute resources on the cloud can be set up with on-demand (highest priced), spot
(bidding based on available compute resource pool and other bidders), and reserved
(commitment to keep using the virtual server for a set period of time) pricing models.
Virtualized
Virtualization allows for efficient use of available compute, storage, and networking hard-
ware and packs in more users without decreasing the experience for a single inhabitant.
We will talk more about virtualization in Chapter 7, “Practical Cloud Knowledge: Install,
Configure, and Manage Virtual Machines and Devices,” where we go through deployment
and management of VMs.
Secure
The ability to have fine-grained control and advanced monitoring enabled makes the cloud
generally secure. There haven't been many instances of security breaches on any of the
major cloud environments. Let's consider a real-world scenario.
A cloud electronic medical record (EMR) application stores and processes electronic
protected health information (ePHI) in the cloud. Any breach of a patient's ePHI must be
reported and the storage entity is often fined. Therefore, the need to keep ePHI secure in
the cloud is a high priority and can become an obstacle for an EMR application vendor
attempting to increase adoption of the application.
To enable increased security for sensitive data assets, public cloud vendors now provide
the ability to have single-tenant virtual servers and dedicated servers for hardware encryp-
tion and key management. A single-tenant virtual server is located on a physical server that
will not spin up virtual servers for any other tenant. These virtual server instances cost
more because available compute resources on the dedicated server cannot be monetized.
For the application vendors, this adds another layer of security since no external process
will have access to the same physical storage and memory resources, which are the most
effective entry points for hackers to gain access to encryption keys and data assets.
Security is now among the top five concerns of companies weighing the adoption of a
cloud solution at some level and companies that have already deeply embraced the cloud
within their IT fabric. There is a heightened awareness for ensuring security of all data that
goes into the cloud for archiving as well as for use within business applications that also run
off the cloud. This is one of the primary reasons we see a plethora of cloud data security
vendors popping up across the cloud domain.
Always Available
No server vendor can guarantee 100 percent uptime. As you can see in Table 2.1, even
99.99 percent uptime would translate into about an hour of downtime over a year.