Reference Architecture for Private Cloud

The Reference Architecture for Private Cloud wiki site on TechNet is driven by the SCD iX Solutions Group. It is a joint effort with the private cloud community at large. This document set is designed to facilitate an organization’s transformation to private cloud as a service delivery enabling set of processes and technologies. Business decision makers, technical decision makers, IT architects and IT Pros interested in private cloud should use relevant documents in this collection to understand the transformation to private cloud in terms of business drivers, potential architectural approaches, and impact on key aspects of IT.

Note:
This document is part of a collection of documents that comprise the Reference Architecture for Private Cloud documentation set which is a community collaboration project. Please feel free to edit this document to improve its quality. If you would like to be recognized for your work on improving this article, please include your name and any contact information you wish to share at the bottom of this page.

The cloud computing principles described in this material refer to the positive attributes typically associated with cloud-based services, such as lower cost and increased agility. These attributes include improved cost transparency through usage-based billing, rapid provisioning or elastic scaling in response to organizational needs or business requirements, and more explicit and mutually understood service levels. Organizations want to know what services they get for the price they pay, and how IT can deliver more effectively against rapidly changing needs.

Complete List of Reference Architecture for Private Cloud Documents:

Overview of Private Cloud Architecture

Private Cloud Technical Overview

What is Infrastructure as a Service?

Private Cloud Reference Model

Private Cloud Principles, Patterns and Concepts

Private Cloud Planning Guide for Infrastructure as a Service (IaaS)

Private Cloud Planning Guide for Service Delivery

Private Cloud Planning Guide for Operations

Private Cloud Planning Guide for Systems Management

Cloud Computing Security Architecture

A Solution for Private Cloud Security

Use the following road map if you want to read the Reference Architecture for Private Cloud document set from beginning to end.

The materials in the Reference Architecture for Private Cloud collection, help the IT service provider to traverse this transformational journey. The materials have a solid foundation in key business drivers. They provide a structured approach to making architectural decisions. The aim is to improve the quality of private cloud infrastructure design while realizing the efficiency gains possible with cloud computing.

Introduction to the Private Cloud Reference Architecture

The Reference Architecture for Private Cloud collection expresses the IT provider’s perspective on delivering cloud services within the enterprise – the approach typically known as “on-premises.”

The Reference Architecture for Private Cloud collection is a resource that helps the IT provider to understand the components of an elastic, on demand environment, guiding principles for realizing it, and offers an approach to designing it with relevant insight into choices and trade-offs.

A fundamental goal of the Reference Architecture for Private Cloud is to provide a common frame of reference and standardized taxonomy. This consistent approach will help you make well-founded strategic and architectural decisions as they adopt cloud computing.

Documentation Approach

The fundamental approach to producing the Reference Architecture for Private Cloud materials was to understand organizational context and define a Reference Model. The Reference Model forms the basis of the Reference Architecture.

The Reference Architecture for Private Cloud uses the classic competing axes of time, cost, and quality as a basis for articulating business drivers, but with the minor modification of replacing the term “time” with “agility,” as “agility” is a better expression of responsiveness. Good examples of business drivers are as follows:

Agility

Reduce Time to Market: Implement new business solutions more quickly so revenue comes in faster.
Better Enable the Solution Development Life Cycle: Speed up business solutions through better facilitation for development and testing and overall faster paths to production.
Respond to Business Change: New requirements of existing business solutions are met more quickly.

Cost

Reduce Operational Costs: Lower daily operational costs for basic needs such as people, power, and space.
Reduce Capital Costs or Move to Annuity-Based Operational Costs: Reduced IT physical assets by using more pay-per-use services.
Transparency of IT Costs: Customers are more aware of what they get for their money.

Quality

Consistently Deliver to Better-Defined Service Levels: Leads to increased customer satisfaction.
Provide Better Continuity of Service: Minimize service interruptions.
Regulatory Compliance: Meeting or exceeding mandatory requirements, which may grow more complex with online services.

These business drivers, along with market forces and customer perspectives, are defined in Reference Architecture for Private Cloud backgrounders. These documents show why IT should be interested in this transformation to a more dynamic state.

The cornerstone of the Reference Architecture for Private Cloud materials is the Reference Model. The Reference Model is defined as a problem domain scope that identifies all domain components – and the relationships between those components. The Reference Model also sets a common vocabulary for the production of a Reference Architecture.

With the Reference Model in place, a Reference Architecture can be produced. The Reference Architecture is split into two aspects based on usage and target roles. One aspect includes architectural principles, concepts, and patterns that apply pervasively to the problem domain. The second aspect defines how those principles, concepts and patterns impact each domain component identified in the Reference Model. The considerations are more planning and design-oriented and hence relevant to architects with specific interests such as infrastructure or operations.

Documentation Structure

The documentation structure specifies the taxonomy of the Reference Architecture for Private Cloud collection and the goal, audience, and content for each document.

Figure 2: Documentation Structure

Reference Model

Audience

The Reference Model is of primary use to those in architect roles, particularly the Enterprise Architect. Other technical decision-makers will find it relevant, as will those who want to absorb a definition of the private cloud problem domain.

Goal

To provide a high-level framework to:

Define the private cloud problem domain from an IT provider’s perspective.
Define a common taxonomy.
Identify the key components of the problem domain and decompose them to the appropriate level of detail.
Provide a basis to describe relationships and dependencies.

Readers of the Reference Model are advised to gain a better understanding of the breadth of components that comprise a private cloud problem domain, plus a frame of reference for taxonomies and logical relationships, before reading other documents in the Reference Architecture for Private Cloud documentation set.

Architectural Principles, Concepts, and Patterns

Audience

The Private Cloud Principles, Concepts, and Patterns document is useful to all architect roles (infrastructure, operations, and enterprise architects) relevant to the scope of private cloud. Solution/application architects will find this material relevant as they interact with the more infrastructure-oriented roles.

Technical decision-makers and others may also find this document helps them understand what constitutes a “dynamic” state for IT and other key concepts relevant to dynamic IT delivery.

Goal

The document contains the guiding principles, concepts, and patterns that form the foundation for the development of a Reference Architecture. Principles are the enduring criteria that define a “dynamic” state from an IT provider’s perspective. The principles are designed to be compelling for the DDC scenario and clearly traceable to business drivers. Concepts and patterns are the architectural strategies utilized to achieve results that adhere to the principles. The principles, concepts, and patterns together form the strategic basis for developing any private cloud design consideration.

The document should provide readers with an understanding of architectural goals for a private cloud and give context for more tactical planning and design-oriented materials.

Planning and Design Guides

Audience

Planning and design guides are focused on specialist roles in four key areas identified in the Reference Model: Infrastructure, Operations, Service Delivery, and Management.

Architects or consultants who are involved in design or planning in these areas should focus on the corresponding portions of the guides.

Goal

For practitioners basing private cloud solutions on the defined principles, concepts and patterns, these documents provide insight into design, trade-offs, decisions, and support. Readers should gain better understanding of the impact of transformation to a more dynamic IT capability and be better equipped to make design decisions to fulfill unique customer requirements.

The following Planning and Design Guides are available as part of the Reference Architecture for Private Cloud collection:

Cross Cutting Issues (Security and Identity Management)

Certain issues, such as security and identity management cut across all components of a private cloud reference model. For this reason there is separate coverage of these topics in the Reference Architecture for Private Cloud document set.

Audience

The Cloud Computing Security Architecture and the forthcoming (January 2012) Cloud Computing Identity and Access Architecture documents are useful to all architect roles (infrastructure, operations, and enterprise architects) relevant to the scope of private cloud. Solution/application architects will find this material relevant as they interact with the more infrastructure-oriented roles.

Goal

Similar to the planning and design guides, these documents provide insight into design, trade-offs, decisions, and support. Readers should gain better understanding of the impact of transformation to a more dynamic IT capability enabled by private cloud and be better equipped to make design decisions to fulfill unique customer requirements.

The following cross-cutting issues architectural documents are or will be included in the Reference Architecture for Private Cloud document set: