Cloud Computing Infrastructure walk through
written by gunther gerlach-2009
Virtual servers in the cloud model. Basically they are providing Infrastructure as a Service. If you need to run your application, you can go to their site, configure your own server with your required configuration and software libraries and they will generate a server on the fly for you! Basically all this magic has come about thanks to virtualization technologies which allow you to create software servers independent of the hardware infrastructure running them. These VMs can be scaled and migrated depending on the need.
The last generation of Cloud computing is a suite of web services that provides resizable compute capacity in the cloud. The web services interface allows businesses to obtain and configure capacity with minimal friction. It provides complete control of your computing resources. These resources need only minutes to obtain and boot new server instances, allowing a quick capacity escalation, both up and down, as your computing requirements change.
Cloud computing has great potential in reducing the cost, increasing utilization and efficiency and simplifying maintenance. Cloud Computing, is an Infrastructure as a service that allows the user to ’switch’ on both processing capacity, and storage as required, like any other. New metrics like Giga-Hertz Hours are used for the pricing models.
The good
Infrastructure investment customers minimize capital expenditure; this lowers barriers to entry, as infrastructure is owned by the provider and does not need to be purchased for one-time or infrequent intensive computing tasks. Services are typically available to or specifically targeted to retail consumers and small businesses.
Location independence device and location independence enable users to access systems regardless of their location or what device they are using.
Multi-tenancy enables sharing of resources and costs among a large pool of users, allowing for:
· Centralization of infrastructure in areas with lower costs (such as real estate, electricity, etc.)
· Peak-load capacity increases (users need not engineer for highest possible load-levels)
· Utilization and efficiency improvements for systems that are often only 10-20% utilized.
On-demand allocation and de-allocation of CPU, storage and network bandwidth
Performance is monitored and consistent, but can suffer from insufficient bandwidth or high network load.
Reliability improves through the use of multiple redundant sites, which makes it suitable for business continuity and disaster recovery. Nonetheless, most major cloud computing services have suffered outages and IT and business managers are able to do little when they are affected.
Scalability meets changing user demands quickly without users having to engineer for peak loads.
Security typically improves due to centralization of data, increased security-focused resources, etc., but raises concerns about loss of control over certain sensitive data. Security is often as good as or better than traditional systems, in part because providers are able to devote shared resources that most customers cannot afford. Providers typically log accesses, but accessing the audit logs themselves can be difficult or impossible.
Sustainability comes about through improved resource utilization, more efficient systems, and carbon neutrality. Nonetheless, computers and associated infrastructure are major consumers of energy.
the biggest Concerns about this new technology
Control: When you give up the management of your infrastructure, you also give up control over it. This reduces your burden but also makes you anxious and vulnerable. Now you have to rely on the guarantees provided by the cloud vendor.
Security: This is the biggest concern as data is the most critical asset of a company. They don’t want to put it in any one else’s hand. Great assurances are required here by the service providers; otherwise they aren’t likely to succeed. Not every provider can afford that unless the industry finds a way to simplify this for them.
Dependability: Today a service provider exists, tomorrow they don’t. Companies cannot rely on such services. They need continuity.
Attributes of Cloud Computing and Applications as a Service
· Elasticity and scalability
· Delivery as a service and service boundary serving as the abstraction layer,
· Ability to expose web services,
· Ability to stack one service onto another (e.g. a start-up on top of Amazon EC2),
· Being optimized for cloud environments with multitenancy and other techniques.
Layers of the Cloud
This new technology well known as cloud computing has a singular list of layers as is described here.
Infrastructure as a Service (IaaS) - basically raw compute and storage services such as Amazon’s EC2 (Gartner calls it: “System Infrastructure Services”.
Platform as a Service (PaaS) - higher-level development environments which abstract the underlying technology and provide for scalability and rapid application development such as Google App Engine or salesforce.com’s force.com.
Software as a Service (SaaS) - classical online software such as Gmail or salesforce.com (for Gartner, “Application Services”).
Information Services - services which process data like Feed burner or Yahoo RSS Feeds.
Business Process Services - like advertising and payroll.
Ecosystem Management and Security Services - various services not really providing stand-alone value but making other services usable for the enterprise, including management and security.
Enabling Technologies - not really publicly exposed services but underlying technology (hardware, OS, etc.) which helps the providers deliver their services.
Conclusion
In summary, Cloud Computing is an inevitable evolutionary step for our industry, while it will likely be around 5 years before we see mainstream adoption, it is an area of the IT World that is worth keeping a watching brief upon, and some early experimentation, particularly for development environment purposes, would be well worth considering.
