The world of cloud computing essentially changes how organizations use technology and how they procure that technology. Cloud computing provides an agile model where resources can be provisioned and consumed to deliver cloud services in an on-demand fashion. There is not necessarily a one-to-one mapping to the on-premises infrastructure, especially if we want to take advantage of the new opportunities that cloud technologies, especially hybrid cloud, offer for building and deploying applications.
With all that flexibility in how design can be done for applications and different environments, organizations adopting cloud computing, hybrid cloud, and related technologies need help to guide them on their decisions, especially during these difficult times of COVID-19. That's why Microsoft has created the Enterprise Scale Cloud Adoption Framework (CAF)  to help organizations move to Azure and adopt Azure DevOps practices.
Organizations adopting cloud computing, hybrid cloud, and related technologies need guidance on their decisions, especially during these difficult times of COVID-19. Read about the Enterprise Scale Cloud Adoption Framework (CAF) from Microsoft.
The framework provides a set of tools such as the aforementioned Azure DevOps, along with guidance and stories to help shape the strategies that customers need to develop in order to move to the cloud. The key here is that the framework doesn't tell us how to move to the cloud. It helps us develop our cloud computing strategies based on our own business needs and risks. The Cloud Adoption Framework helps an organization develop plans for the business, culture, and technical change that comes with moving to the cloud.
There are seven phases in the Enterprise Scale Cloud Adoption Framework.
The “strategy” phase is where we need to meet with business stakeholders and key executives and document their motivations for cloud adoption. They might be looking for cost savings by moving to the cloud or wanting to improve customer experience and increase business agility.
Motivations typically involve a desire to migrate or to innovate, but there is likely a desire for both. It also consists of documenting specific business outcomes, like fiscal outcomes, which might involve closing a data center to save costs and to avoid future refresh cycles for on-premises hardware. The strategy phase is also where they choose their first Cloud Adoption Framework project. The guidance in the strategy phase of the Cloud Adoption Framework will help you align your first project to the identified goals of the stakeholders.
The second phase is to develop a cloud adoption plan. This plan will guide the technical efforts using tools such as Azure DevOps. It starts with creating an inventory of the digital assets that the organization owns today. This is called the digital estate. The next step is organizational alignment where you map key resources to the various roles required for cloud adoption and governance.
Accordingly, the skill gap can be addressed. A set of new responsibilities will arrive with digital transformations, so assessing existing skills within your organization and planning for training will help keep you on schedule, and the planning phase results, according to a plan. The framework enables you to define the prerequisites and prioritize workloads, iterations, and timelines to move to the cloud.
The third phase is called “ready”, which involves readying the cloud environment or setting up the foundations for Azure. This is where actions such as establishing a management hierarchy is done by planning management groups, subscriptions, and resource groups so you can create naming conventions and tags. The framework helps develop a blueprint to create what's called a migration landing zone; basically, an environment in Azure that's been prepared to host workloads migrated from on-premises datacenter or other clouds.
Microsoft has recently developed a completely new approach on the landing zone, also known as an Enterprise-Scale landing zone. It is a logical construct capturing everything that must be true to enable application migration and greenfield development at an enterprise scale in Azure. The core design principles are as follows: 
- Policy-driven governance
- Subscription democratization
- Single control and management plane
- Align Azure-native design and roadmap
- Application-centric and archetype neutral
In addition to the principles, Enterprise-Scale CAF also provides design considerations, guidelines, and recommendations.
The following eight critical design areas are intended to support the translation of customer requirements to Azure constructs and capabilities, and to address the mismatch between on-premises infrastructure and cloud design, which typically creates a dissonance and friction concerning cloud adoption.
Below are the eight key design areas: 
A - Enterprise enrolment and Azure AD tenants
B - Identity and access management
C - Management group and subscription organization
D - Network topology and connectivity
E - Management and monitoring
F - Business continuity and disaster recovery
G - Identity and access management
H - Platform automation and DevOps
The high-level design is depicted in the following diagram in detail: 
Figure 1: The Cloud Adoption Framework and Enterprise-Scale Landing Zone Architecture 
The “migrate” phase is the fourth stage of CAF. The framework provides a checklist to help identify prerequisites that need to be satisfied. Then it allows us to choose the migration method and features that we can use to govern and secure the environment.
Depending on the workload, you may be able to lift and shift applications and workloads with minimal changes, or you may need to re-architect workloads or even rebuild applications because there are too many changes required. The framework provides the Azure Migration Guide as a starting point for lift-and-shift-type of migrations, and the framework also guides expanded scope scenarios, like migrating multiple data centers or moving data offline using a service called Azure Data Box.
COVID-19 has created unprecedented challenges and the “migrate” phase has been on the rise with most customers moving toward Azure WVD solutions as the usage of cloud services has significantly increased. Customers who have already built their Azure foundation based on Enterprise-Scale have been able to adopt these cloud services and cloud technologies at a rapid pace due to the agility which Enterprise-Scale provides for them.
Once the “migrate” phase has been completed, the “innovate” phase starts. Most cloud adoption efforts focus on migration and modernization of existing workloads, but innovation is where you can create business value, as well. The framework provides the Azure Innovation Guide, which can help you with engaging customers and managing their feedback using tools like Azure DevOps. It will also guide you with best practices on building engaging applications and developing data solutions. It outlines a methodology for innovation and tools within Azure that align with that methodology.
The most crucial phase starts after the innovate phase which is called the govern phase. Cloud governance should complement existing policies made for on-premises environment or hybrid environment, but the guidelines will change over time as we move more and more workloads to the cloud.
Adopting the cloud is a journey, not a destination, and cloud governance creates the guardrails that keep the company safe during that journey  as corporate policies and key performance indicators (KPIs) drive cloud governance.
The five disciplines of cloud governance— cost management, security, identity, resource consistency, and deployment acceleration— support the policies that the “govern” phase establishes.
The final phase is called “manage” that develops the business and technical approaches needed for the ongoing operation. It starts with establishing a management baseline that defines the tools and processes required for operations management such as Azure Arc.
Defining business commitments is about agreeing with the business on things such as the criticality of workloads and the impact of outages. The framework provides an operations management workbook to helps us capture these measures. The framework also offers actionable best practices for Azure server management and hybrid cloud monitoring using tools such as Azure Monitor, Azure Automation, and Event Hubs.
The Enterprise Scale Cloud Adoption Framework is a massive library of guidance and best practices on how to move to the cloud. While most of it involves Azure technologies such as Azure Monitor, Azure Migration, Azure Automation, and Azure Data Box, there's a lot of advice available on cloud adoption.
At the HCLTech Microsoft Business Unit, we have adopted the Enterprise-Scale approach for our customers to provide the benefits of cloud-native designs. HCLTech has created its own flavor of Enterprise-Scale CAF to optimize cost saving for the customer using HCLTech North Star Cost optimization framework and hybrid CAF.
Hybrid Enterprise-Scale CAF is a framework that HCLTech had adopted based on the lessons learnt in the field while implementing CAF. In his blog post, Microsoft’s Dominik Zemp rightly said that Enterprise-Scale is not something which you will implement if your organization is very much controlled by IT.
There is a mandatory layer to enable a centralized IT team to control the entire cloud adoption, including all networking aspects, identity, security, and cloud monitoring for all applications etc.
Enterprise-Scale might not be the best implementation option for Azure landing zones. This is because such an ‘IT-controlled approach’ would not align with the enterprise scale design principles. We have also learned the same lesson on the field. Hence, at HCLTech, we have adopted the Hybrid CAF approach based on the customer’s journey to the cloud.
-  Microsoft (2020) Cloud Adoption Framework for Azure [Online]. Available at: https://docs.microsoft.com/en-us/azure/cloud-adoption-framework/ (Accessed: 06 May 2020)
-  Microsoft (2020) Cloud Adoption Framework enterprise-scale design principles [Online]. Available at: https://docs.microsoft.com/en-us/azure/cloud-adoption-framework/ready/enterprise-scale/design-principles (Accessed: 06 May 2020)
-  Microsoft (2020) Cloud Adoption Framework enterprise-scale design guidelines [Online]. Available at: https://docs.microsoft.com/en-us/azure/cloud-adoption-framework/ready/enterprise-scale/design-guidelines (Accessed: 08 May 2020)
-  Microsoft (2020) Cloud Adoption Framework enterprise-scale landing zone architecture [Online]. Available at: https://docs.microsoft.com/en-us/azure/cloud-adoption-framework/ready/enterprise-scale/architecture (Accessed: 08 May 2020)
-  Microsoft (2020) Govern methodology for the cloud [Online]. Available at: https://docs.microsoft.com/en-us/azure/cloud-adoption-framework/govern/methodology (Accessed: 08 May 2020)
-  Microsoft (2020) Start with Cloud Adoption Framework enterprise-scale landing zones [Online]. Available at: https://docs.microsoft.com/en-us/azure/cloud-adoption-framework/ready/enterprise-scale/ (Accessed: 08 May 2020)
-  Microsoft (2020) When to use Enterprise-Scale? [Online]. Available at https://techcommunity.microsoft.com/t5/azure-architecture-blog/when-to-use-enterprise-scale/ba-p/1595710 (Accessed: 08 May 2020)