Computerworld - When IT consultancy OpenCredo set out to launch three new applications within seven months for a major insurance underwriter, it had three goals in mind: Trim development time from the usual years-long pace, allow for frequent changes from the client, and build a system that can handle unpredictable traffic spikes.
By using the Cloud Foundry open-source framework along with other open-source software, OpenCredo eliminated "heavy lifting" such as configuring virtual machines and adjusting the size of storage volumes, says CEO Russell Miles. The framework allowed developers to write code locally, share it with the client, and automate the integration, testing, and deployment of application components.
Among other advantages, Cloud Foundry makes it easier to scale an application by adding more instances without downtime, Miles says. Because of the way it works with other open-source software, new features can be added in minutes rather than hours.
Even with all those benefits, open-source cloud frameworks like Cloud Foundry are a work in progress. Many manage only physical servers or stand-alone applications, leading customers who need more sophisticated capabilities to create their own frameworks. However, they offer compelling value because they mask the complexity of cloud computing setups, and the open-source model is an attractive way to do that.
Understanding the Basics
The term "framework" is used to loosely describe collections of anything from development tools to middleware to database services that ease the creation, deployment and management of cloud applications. Those that work at the level of servers, storage and networks are infrastructure-as-a-service (IaaS) frameworks. Those that operate at the higher level of applications are platform-as-a-service (PaaS) frameworks.
Among the most popular IaaS frameworks are OpenStack, Eucalyptus, and the Ubuntu Cloud infrastructure. Citrix recently announced it was making its formerly proprietary CloudStack IaaS platform part of the open-source Apache project. Gartner analyst Lydia Leong wrote in her blog that this is "big news" because CloudStack is much more stable and production-ready than the "unstable" and "buggy" OpenStack.
Popular PaaS frameworks include Heroku, Cloud Foundry (backed by VMware), and Red Hat's OpenShift, which is built on a foundation of Red Hat Enterprise Linux with support for a variety of languages and middleware through the use of "cartridges."
Customers often use multiple frameworks and associated tools. One example is the use of OpenStack to provision virtual machines, and Opscode Chef to create "recipes" describing how servers should be configured, says Opscode co-founder Jesse Robbins. The further up the "stack" a platform operates, the less work the customer must do, but they also have less control over the infrastructure components, says Matt Conway, CTO at online backup vendor Backupify.
Beyond easing cloud creation, most frameworks claim to make it easier to move cloud deployments among public and private clouds to get the lowest cost and best service. For example, Eucalyptus is meant to provide an Amazon EC2-compatible API that runs on top of Ubuntu Linux (the version of Linux underpinning the Ubuntu Cloud), "so apps authored for EC2 should be transplantable to one's own data center running Eucalyptus," says Conway. "Deltacloud was an initiative by Red Hat to create a 'cloud API' to abstract your application away from vendors like Amazon, and it would proxy your requests to the actual Amazon API."
For online storage vendor CX, OpenStack provides the flexibility to use other cloud vendors besides Amazon "if [Amazon's] services become too expensive or otherwise unsuitable," says CX CTO Jan Vandenbos.
Anthony Roby, a senior executive in Accenture's advanced systems and technology group, says the word "framework" is often misused, and offerings such as Eucalyptus or OpenStack are "not frameworks at all," but "products you can extend or use to build your own infrastructure cloud." However, most observers define frameworks as software building blocks used to create cloud-based services for users.
Choosing an Open-Source Framework
1. Evaluate which components of a "framework" you need, as well as the level (i.e., infrastructure, platform or both) at which you need to reduce your workload.
2. Evaluate the level of support and professional services you'll need.
3. Check support for the specific cloud providers you might want to use, and whether your platform supports the added services (such as replication) your applications may require.
— Robert L. Scheier