Introduction - Hybrid Connectivity


A modern organization uses extensive array of IT resources. In the past, it was common to host these resources in an on-premises data center or a colocation facility. With the increased adoption of cloud computing, IT resources are delivered and consumed from cloud service providers over a network connection. In some cases, organizations have opted to migrate all existing IT resources to the cloud. In other cases, organizations maintain IT resources both on premises and in the cloud. In both cases, a common network is required to connect on-premises and cloud resources. Coexistence of on-premises and cloud resources is called hybrid cloud and the common network connecting them is referred to as a hybrid network. Even if your organization keeps all of its IT resources in the cloud, it may still require hybrid connectivity to remote sites.

There are several connectivity models to choose from. Although having options adds flexibility, selecting the best option requires analysis of the business and technical requirements, and elimination of options that are not suitable. Requirements can be grouped together across considerations such as: security, time to deploy, performance, reliability, communication model, scalability, and more. Once requirements are carefully collected, analyzed, and considered, network and cloud architects identify applicable AWS hybrid network building blocks and solutions. To identify and select the optimal model(s), architects must understand advantages and disadvantages of each model. There are also technical limitations that might cause an otherwise good model to be excluded.

To simplify the selection process, this whitepaper guides you through each key consideration in a logical order. Questions used to collect requirements are listed under each consideration. The impact of each design decision is identified along with possible solutions. Decision trees are presented for some of the considerations as a method to aid decision-making process, eliminate options, and understand consequences of each decision. The whitepaper also applies the whole connectivity model selection and design process to a scenario covering a hybrid use case. It helps you to see how the process is executed end-to-end in a practical example.

This whitepaper is intended to help you select and design the most optimal hybrid connectivity model. This whitepaper is structured as follows:

  • Hybrid connectivity building blocks - overview of AWS services used for hybrid connectivity.

  • Connectivity selection and design considerations - definition of each connectivity model, how each impacts the design decision, requirement identification questions, solutions, and decision trees.

  • A customer use case - an example of how to apply the considerations and decision trees in practice.