Wednesday, February 06, 2013

Baby Steps Towards Cloud Computing

Baby Steps Towards Cloud Computing

Determine the Cost of Operating Applications

Teasing out all the hidden costs of running an application may take some work, but is absolutely critical in taking the first step toward cloud computing. Without an accurate picture of the cost, an internal application may appear less expensive to run than it actually is and conversely a cloud computing application more expensive. This is important because the more costly the application is to run, the better candidate it is for cloud computing. But again this is only the first step.

Determine the Cost of Moving the Application

 Current operating costs can not be the only criteria to use when identifying candidate applications to move to the cloud. Even if you identify an application that could be run much less expensively on the cloud, the one‑time costs of moving it may be prohibitive. Before you begin, there are many questions you need to answer about how the application is integrated with the rest of the infrastructure:
•How many sources of data does the application have?

•Where is this data coming from? User entry? Database? Other applications?

•How many integration points does the application have with other applications?

•To how many other applications does this application feed data?

•Are the interfaces standardized using middleware or API’s or custom?

•How well documented are the interfaces?

•Are the people who developed them still available to answer questions?

All these factors determine the next step in estimating how expensive it will be to move applications to the cloud.

Determine Compatibility Issues

 The third step in analyzing which applications to move to the cloud is to determine compatibility issues. Cloud computing depends on virtualization. Virtualization software comes from vendors like VMware, Citrix, Microsoft, Novell, and Oracle. Not all applications are certified to run on top of all brands of virtualization software. Determining what virtualization software your application can be run on can make choosing Cloud computing vendors much easier since not all vendors support all platforms.

Determine Latency Issues

 One of the biggest complaints people will have when working with computers is response time. Delays in the real and perceived time between a request for data and its delivery have driven data center spending for years. The assumption that most people seem to make is that data should be instantly transmitted between one point and another, which is impossible. But keeping the wait within acceptable bounds should be the goal of any good IT organization. So any time the physical location of an application server changes, latency issues will need be considered and occasionally addressed. 

This can be complicated. Some of these issues include:
•Application performance ‑ although it is not strictly a part of the cloud, poor application performance can impact response time and acceptance of the cloud solution. A poorly written data base request can have a measurable impact on response time, even though it has nothing to do with the cloud. 

•Application chattiness ‑ some applications may communicate back and forth as much as a 1,000 times between client and server before completing a cycle. This may not have much impact on response time in a local area network, but in a wide area network it can be significant.

•Network performance ‑ again the connection between the end user and the provider’s data center is technically not part of the cloud but should be addressed. Among the factors that influence network performance are:
◦Transport medium ‑ The physical connection between points, whether it be twisted pair, coaxial cable, microwave, or optical fiber (and the myriad of possible combinations), introduces different levels of delay.

◦Packet size ‑ Larger packets can take longer to send and receive than smaller ones

◦Propagation delay ‑ The amount of time it takes for data to travel from one point to another.

◦Router overhead ‑ The time it takes routers to examine and update packets can add to delay. 

•Cloud performance ‑ the devices in the cloud provider’s data center and virtualization software can also effect latency.

Cloud Pricing Reflects Utilization

 Looking again at the National Institute of Standards and Technology (NIST) definition for cloud computing, one idea that stands out is that customers should only pay for what they use. In an additional part of the definition (yes! there is more) NIST goes on to suggest true cloud computing be metered to encourage optimal use of resources. The only problem with this is that there is no agreement in the marketplace about what exactly to meter.
Until this sorts itself out there will be almost as many methods of pricing as there are vendors. For example, to effectively know how much you will spend with every month it is helpful to know the duration of your VPN connection, the amount of data you expect to transfer in, the amount of data you expect to transfer out, how many Gigabytes of storage you expect to use, the operating system, that database or file system, how many applications you are going to run and how much CPU and Memory they will use. on the other hand bases its pricing primarily on the number of users, with some limits on applications and storage. Other vendors such my company, ACS Business Application Solutions, simplify things for our users by asking fixed monthly fee for specific periods of use time.
After determining what applications cost to run on your terms you need to begin to analyze what your applications will cost to run under someone else’s terms. This means starting to collect and analyze lots of system data. This can be done while you take the next step and consider what your infrastructure architecture looks like today and what it will eventually look like.

Performance Monitoring

 Closely related to latency issues is performance monitoring. How performance is measured across the cloud is an important consideration since most relationships between cloud user and cloud provider will be governed by a service level agreement (SLA). Most typically this agreement will have a performance clause. Measurement is intrinsically complex because the user’s data transfer path is likely to involve multiple layers of the network and application stack and to cross multiple network domains that are independently administered. Determining the right tools to perform network monitoring and what is being measured ‑ end‑to‑end, point to point, bandwidth, throughput, or absolute capacity ‑ is worth considering up front. 

Cloud Architecture Options

 With all the hype in the marketplace it is easy to think of cloud computing as an all‑or‑nothing proposition but it is not. Like real clouds, computing clouds come in many sizes, and shapes..
•Public Cloud ‑ The public cloud is the least traditional but most publicized kind, in which a service provider makes computing resources, such as servers, storage, and applications, available to anyone from the general public over the Internet. Typical public cloud providers are very large companies who want to deal with a large numbers of customers using standardized service level agreements and offerings. This offering is usually has the lowest cost and most potential for scalability. In transportation terms, a public cloud is like a passenger train, commercial airliner, or a bus.

•Private Cloud - An organization that needs or wants more control over its computing or wants a more specialized service can build a private cloud, which provides hosted services to authorized users behind a firewall. This can be done internally as well as externally, although some of potential cost savings are lost in this approach. In transportation terms, a private cloud is like a limo, taxi, or fractional plane ownership.

•Community Cloud - The cost of the cloud is shared by several organizations with similar needs, such as HIPAA compliance, that can not be found on a public cloud. A community cloud can be internal to one of the organizations or hosted by a third party such as ACS. In transportation terms, a community cloud is like car pooling.

•Hybrid Cloud - A fourth model, the hybrid cloud, is maintained by both internal and external providers and is some mix of public cloud, private cloud, and community cloud. Continuing the transportation metaphor, the hybrid cloud is like taking a car to the airport, a bus to the terminal, an airplane to another city, and a taxi to the hotel.

Whether consciously or not, most IT shops today have an architecture that includes some form of a hybrid cloud. The vast bulk of the infrastructure may involve internal applications but some parts of the organization may also use for sales, Gmail for email, Linked In for recruiting, Double Click for advertising, etc. In other words, many organizations are already moving towards cloud computing, though in some cases in a piecemeal way. It is worth considering how a more deliberate and thorough analysis of the fit between existing applications and cloud resources might serve your organization.

The Cloud is Freedom

 Most organizations are headed for the cloud, because besides cost savings, cloud computing offers freedom. The cloud offers the freedom to streamline expenses and increase profits. A cloud can be up and running in a few days, and with the right provider can be more scalable and secure than an internal environment. The cloud also offers freedom from having to justify capital expenditures and unpredictable expenses. It can free the IT organization from maintenance upgrades, security updates, capacity planning, disaster recovery, and release management to concentrate on more valuable work.
With the advantages of cloud computing so clear, if you decide to move forward again you are in good company. IDC announced IT spending on cloud computing will reach $42 billion by 2012.(5) By that time they estimate cloud computing will capture 25% of IT spending growth and amount to 33% of spending growth in 2013.
Getting started is straightforward and using the approach outlined in this article is low risk. There is no reason not learn more about the benefits of cloud computing‑‑the sky’s the limit.

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