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Negotiating a cloud service-level agreement is certainly important, but enforcing one is just as critical. SLA administration is effectively a specialized form of application performance management in the cloud. And if your management framework selection is off, SLA administration can eat up all expected operations savings in a cloud project -- minimizing one of the biggest benefits of cloud services.
Cloud SLA management is complicated by the fact that nearly all cloud applications are federations of multiple providers. At a minimum, cloud application performance depends on how it functions across the boundaries between the cloud provider, the network and the users. These elements are difficult to measure because the user lacks full management visibility into the cloud and the global network or virtual private network (VPN) that provides connectivity. If multiple cloud providers are involved, or if it's a hybrid cloud architecture, it becomes even more complicated.
By enabling the IT giants to offer easily administrable SLAs, it compels other cloud providers to consider their own tools for SLA administration.
Enterprises take three paths when administering an SLA, each with its own benefits and risks. First, they attempt to use existing management tools to collect information on both cloud application program interfaces and application/network application program interfaces (APIs). Second, they purchase a cloud management tool that gives them broad visibility through a single graphical user interface (GUI). The third, and likely most effective, path is to use a "management window" into their cloud provider's system.
The problem with administering an SLA using existing management tools
With the expectation of saving time and cost, most users' instincts are to adapt their current management systems to administer a cloud SLA. While this approach preserves technology and operating practices, it adds another layer of management to current application support processes. Any cloud service requires management, but users must also manage any application components and middleware they contribute to the cloud and the network over which the cloud is accessed.
While most enterprises use flexible management tools that can integrate all of these sources into a single system, this integration may not help isolate performance problems. Therefore, this approach doesn't address enforcing the terms of an SLA.
The 'window' into cloud SLA management
The problem with using traditional, third-party management tools to enforce an SLA is largely a matter of visibility. An effective management system, at a minimum, must provide detailed performance information at the boundaries between the user, the cloud provider(s) and network provider(s) to isolate responsibility for problems. Since the user is disconnected from the cloud provider's link to the network, monitoring this boundary can prove difficult or impossible.
On the other hand, the cloud provider has visibility both into its own IT resources and into the boundary between itself and the network provider. Therefore, another solution to SLA administration is to use cloud-provider-specific management tools as the primary source of performance information.
Most larger cloud providers offer enterprises a "window" into their management systems. This window could be used in conjunction with the user's own application management tools to obtain full management visibility for SLA administration. For higher-level cloud services (Platform as a Service and especially Software as a Service), the user's contribution to monitoring application performance is less extensive, and it may be possible to fully administer an SLA with the cloud management window alone.
The "sweet spot" for the management-window approach is probably PaaS, which may be why companies like IBM are focusing increasingly on PaaS as their preferred cloud service offering. System software is normally a major element in an application management strategy, and it's part of a PaaS cloud. That means a cloud provider's management console could provide enough management visibility to support effective user management of SLAs.
The future of cloud SLA management
The newest option for administering an SLA is to use a "cloud management system," which is a specialized management tool designed to be integrated with on-premises resources, cloud resources and application components to provide a unified view. This system is a positive step toward what some believe will be the future of application performance management and SLA enforcement because it synthesizes a cloud-centric vision of the application by drawing data from all the possible sources.
The challenge is that there are no management standards for the cloud and no consistent management interfaces for system platforms, networks or application components. That makes cloud management systems an exercise in customization, particularly if the cloud computing provider chosen isn't someone like Amazon Web Services, which most cloud management tools will support.
More IT vendors are offering both public and private cloud support, and these vendors (IBM and HP, for example) also offer integrated cloud management systems. Because these systems are designed to support hybrid clouds based on the IT vendor's public and private cloud tools, they typically have full visibility into all critical service points and can collect SLA data for review and resolution of performance problems.
And this common-architecture, hybrid cloud concept is the most promising development in cloud SLA enforcement. By enabling the IT giants to offer easily administrable SLAs, it compels other cloud providers to consider their own tools for SLA administration.
In the long run, the most significant truth about SLA administration may be that system software must create the bridge between management's view of the provider and the user's view. Application performance management is nearly always a function of the software platform -- making SLA administration easier at the technology integration level for PaaS. Since PaaS is also the easiest to hybridize, developments here will lead the charge in creating a framework for cloud SLAs that can be meaningful to the buyer and give one cloud provider an edge over its competition.
About the author
Tom Nolle is president of CIMI Corp., a strategic consulting firm specializing in telecommunications and data communications since 1982.