Chapter 3 - Understanding Cloud Computing
Match Strategy
Adding IT resource capacity in small increments, as demand increases.
Lead Strategy
Adding capacity to an IT resource in anticipation of demand.
Lag Strategy
Adding capacity when the IT resource reaches its full capacity.
IT resource
Is a physical or virtual IT-related artifact that can be either software based, such as a virtual server or a custom software program, or hardware-based, such as a physical server or a network device.
Cloud computing
Is a specialized form of distributed computing that introduces utilization models for remotely provisioning scalable and measured resources.
cloud service Consumer
Is a temporary runtime role assumed by a software program when it accesses a cloud service. Ex: Software program, workstation, laptop, mobile device...
Organizational Agility
Is the measure of an organization's responsiveness to change.
cloud provider
Party that provides cloud based services.
could consumer
Party that uses the cloud based services.
Grid Computing
Provides a platform in which computing resources are organized into one or more logical pools. These pools are collectively coordinated to provide a high performance distributed gird, sometimes referred to as a "super virtual computer."
scaling down
Replace IT resources with antoher that has a lower capacity.
scaling up
Replacing IT resources with another that has a higher capacity.
Capacity
Represents the maximum amount of work that an IT resource is capable of delivering in a given period of time.
SUMMARY
- control exercised by a cloud provider over its plataform makes operational governance limited - portability can be limited by dependency - geographical location of data and It resources can be out of a cloud consumer's control. regulatory and legal concerns.
Risks and Challenges
1. Increased Security Vulnerabilities The moving of business data to the cloud means that the responsibility over data security becomes shared with the cloud provider. The remote usage of IT resources requires an expansion of trust boundaries by the cloud consumer to include the external cloud. 2.. Reduced Operational Governance Control: cloud consumers vc on premise IT resources (longer geographical distances 3. limited portability between cloud providers: moving cloud consumer IT resources and data between clouds. 4. Multi-Regional Compliance and Legal Issues: Third-party cloud providers will frequently establish data centers in affordable or convenient geographical locations. Cloud consumers will often not be aware of the physical location of their IT resources and data when hosted by public clouds. 5. Legal Issues: Another potential legal issue pertains to the accessibility and disclosure of data. Countries have laws that require some types of data to be disclosed to certain government agencies or to the subject of the data
Goals and Benefits
1. Reduced Investments and Proportional Costs: elimination or minimization of up-front commintments 2. Increased Scalability: allocate IT resources to cloud consumers, on demand or via cloud consumer's direct configuration. (related to costs benefits) 3. Increased Avalibility and Reliability: provide extensive support to minimize/eliminate outagesand minimize run-time of failure. (can reover more and accesible for longer periods)
Over-provisioning
A discrepancy between the capacity of an IT resource and its demand can result in a system becoming inefficient.
Under-provisioning
A discrepancy between the capacity of an IT resource and its demand can result in a system becoming unable to fulfill user needs.
On-premise
An IT resource that is hosted in a conventional IT enterprise within an organizational boundary.
Business Drivers
Capacity Planning Cost Reduction Organization Agility
Capacity Planning
Capacity planning is the process of determining and fulfilling future demands of of an organizations IT Resources, products and services.
scaling out
Horizontal allocation of resources.
scaling in
Horizontal releasing of resources.
Clustering computing
Is a group of independent IT resources that are interconnected and work as a single system. system failure is reduced while avalibility and relibility are increased
horizontal scaling
Scaling out and in; The allocating or releasing of IT resources that are the same type.
vertical scaling
Scaling up and down; When existing resources are replaced with higher or lower capacity.
Acquiring new infrastructure and the ongoing cost of ownership
What are the two types of cost that are related to IT resources.
on-premise resources can
access and interact with cloud-based IT resources, moved to the cloud or be redundant based on premise and cloud.
Cost Reduction
cost of acquiring new infrastructure and the cost if its ongoing ownership
What's cloud computing?
introduces utilization models for remotely provisioning scalable and measured resources