Cloud technology is one of the most disruptive technologies of the decade. Clouds offer so
many benefits to all types of businesses ranging from small-sized to large multinational
enterprises. If you haven’t still taken the step of moving to a cloud environment, your
business might be missing something great. Let me introduce you to the concept of cloud
migration and to the great benefits it can offer your business.

What is Cloud Migration?

Cloud Migration is the technical jargon for the process of transitioning or transferring to cloud
computing. Usually, the cloud migration process is of two folds.

1. Transitioning from a legacy system to the cloud
2. Transferring from one cloud service model/ deployment model/ usage model to
   another
   Regardless of the process used, cloud migration involves moving data, applications,
   business processes, and replacing technology infrastructure partially or completely.

What are the key benefits of Cloud Migration?

The National Institute of Standards and Technology (NIST), a technology agency that is part
of the US Department of Commerce that works with industry to develop and apply
technology, measurements, and standards, lists five characteristics of cloud computing.

1. Broad network access: Consume services from anywhere
2. On-demand availability based on the consumer’s self-service: Consume services
   whenever you want
3. Virtualization and resource pooling: Pool the infrastructure, applications, and virtual
   platforms
4. Rapid elasticity: Share pooled resources to enable the use of greater numbers of the
   same type of resources to meet demand
5. Measured service usage: Pay for the service you consume as you consume it
   The above five characteristics illustrate the key benefits of cloud migration to any business of
   any scale, belonging to any categorization. In addition, the following benefits lie based on
   the combination of the service model and migration strategy used by your business.

What is the Best Cloud Migration Strategy for My Business?

However, a cloud migration strategy should be adopted for your business to harvest the best
opportunities and profits. There are six cloud migration strategies popularly known as ‘6 R’s
of Cloud Migration’ in the industry.

1. Rehost (Lift and Shift)
   The approach of lifting the whole enterprise architecture stack of your business with
   zero modifications and shifting it from on-promises hosting to the cloud is known as
   ‘Rehosting.’ Simply, this is the strategy of migrating to an Infrastructure as a Service
   (IaaS) model. Companies with no long-term strategy to harness advanced cloud
   capabilities and with regular peak schedules and market trends or expect no long-
   term evolution on business processes are well suited for rehosting.
2. Replatform
   This strategy involves taking advantage of the Platform as a Service (PaaS) model
   and porting existing application components into cloud-native analogs. Replatform is
   an optimization of rehosting. An example is transitioning from a legacy database
   system to a compatible cloud-native database service.
3. Repurchase
   Simply, the repurchase strategy represents the transfer of existing services to
   Software as a Service/s (SaaS) model. Moving from an in-built CRM software to
   Salesforce or Microsoft Dynamics is an example of repurchasing.
4. Refactor (Rearchitect)
   This means that everything from the code up is rearchitected, including the
   application’s relationships with infrastructure and database, and build from scratch to
   take advantage of cloud capabilities and benefits.
5. Retire
   Decommission of redundant and/ or useless legacy tools at the stage of assessment
   of cloud readiness of a company is known as Retire.
6. Retain
   Some applications, data, or software platforms are vulnerable to migrate to the cloud
   due to unassessed security and compliance restraints. Therefore, retaining the
   vulnerable components unexposed to public cloud and revisiting cloud migration with
   only what makes sense to your business and with the workable cloud deployment
   model, is the sixth ‘R’ of cloud migration strategy.

It is easy to understand the specialized benefits of cloud migration to your business by
mapping the cloud migration strategies to the cloud service models. A holistic view on how
the Rehosting, Replatforming, and Repurchasing is mapped with the cloud service models in
terms of increased levels of abstraction can be illustrated as follows.

Therefore, as per the diagram, the benefits of the Replatform coincides with the benefits of
the PaaS model; the benefits of Repurchase coincides with the benefits of the SaaS model,
and the benefits of Rehost coincides with the benefits of the IaaS model.

Benefits of Migration to Cloud

One Cloud Service will list down the many benefits of migrating to the cloud, categorizing them as below.
However, these benefits differ from the cloud strategy and cloud service model you use.
Therefore, listing them separately under each strategy and the model will help you
understand it better.

Benefits of migration to IaaS (adopting ‘Rehost’ strategy)

• Curtail additional expenses associated with data center maintenance, on-premises infrastructure maintenance, and data center team management.
• Ability to scale up and down the storage capacity, improving the scalability of the business.
• Reducing latency independent of location.
• Sandbox environment: Redundancy, data integrity, and security of data.
• A robust disaster recovery plan is managed and monitored by the cloud service provider.

Benefits of migration to SaaS (adopting ‘Repurchase’ strategy)

• It enables you to focus on business operations, rather on infrastructure management or hardware maintenance.
• Flexible consumption-based price model over, paying the infrastructure upfront.
• Availability of database and storage as standard, ready-made, off-the-shelf services for application usage.
• Ability to increase efficiency and productivity via automation.

Benefits of migration to PaaS (adopting ‘Replatform’ strategy)

• Zero or minimum up-front infrastructure costs for hosting utility applications.
• No up-front license, packaging, or maintenance costs for utility applications that are available as SaaS.
• Ability to increase cash flow efficiencies by automating mundane tasks.
• Ability to focus on business operations and core business values and not be distracted by IT.

The benefits listed above overlap and cascade in a similar way the cloud models stacked in
the diagram. For example, the benefits of the ‘Repurchase’ strategy are a union of both lists
of benefits of IaaS and SaaS.

Why ‘Refactoring’ strategy? and What are the Benefits?

Say, your company needs to replicate your legacy system completely to take better
advantage of the cloud-based features and the extra flexibility that comes with them while
developing a customized business solution specialized exclusively to the business. Then
Refactoring is the best option for your use case.
Most of the benefits of refactoring are delivered in the long run, such as listed below.

• Ensure an over-time reduction in costs matching resource consumption with the demand, and eliminating the waste. This leads to a far better and more lasting return on investment compared to the less cloud-native applications.
• Inheritance of increased resilience of the cloud.
• Enables to leverage applications with auto-scaling features of cloud services.
• High compatibility with future cloud versions.

The benefits of Retain and Retire have not been discussed in this article since they are two
stages in the cloud migration process that inhibits the achievement of cloud migration, as
discussed above.

However, in addition to a cloud migration strategy, businesses need to decide the right cloud
deployment model and cloud migration tools and services to plan and execute the migration
process, for reaping the maximum benefits of cloud migration.