AWS Security Blog
Disaster recovery compliance in the cloud, part 1: Common misconceptions
Compliance in the cloud can seem challenging, especially for organizations in heavily regulated sectors such as financial services. Regulated financial institutions (FIs) must comply with laws and regulations (often in multiple jurisdictions), global security standards, their own corporate policies, and even contractual obligations with their customers and counterparties. These various compliance requirements may impose constraints on how their workloads can be architected for the cloud, and may require interpretation on what FIs must do in order to be compliant. It’s common for FIs to make assumptions regarding their compliance requirements, which can result in unnecessary costs and increased complexity, and might not align with their strategic objectives. A modern, rationalized approach to compliance can help FIs avoid imposing unnecessary constraints while meeting their mandatory requirements.
In my role as an Amazon Web Services (AWS) Compliance Specialist, I work with our financial services customers to identify, assess, and determine solutions to address their compliance requirements as they move to the cloud. One of the most common challenges customers ask me about is how to comply with disaster recovery (DR) requirements for workloads they plan to run in the cloud. In this blog post, I share some of the typical misconceptions FIs have about DR compliance in the cloud. In Part 2, I outline a structured approach to designing compliant architectures for your DR workloads. As my primary market is Canada, the examples in this blog post largely pertain to FIs operating in Canada, but the principles and best practices are relevant to regulated organizations in any country.
“Why isn’t there a checklist for compliance in the cloud?”
Compliance requirements are sometimes prescriptive: “if X, then you must do Y.” When requirements are prescriptive, it’s usually clear what you must do in order to be compliant. For example, the Payment Card Industry Data Security Standard (PCI DSS) requirement 8.2.4 obliges companies that process, store, or transmit credit card information to “change user passwords/passphrases at least once every 90 days.” But in the financial services sector, compliance requirements for managing operational risks can be subjective. When regulators take what is known as a principles-based approach to setting regulatory expectations, each FI is required to assess their specific risks and determine the mitigating controls necessary to conform with the organization’s tolerance for operational risk. Because the rules aren’t prescriptive, there is no “checklist for achieving compliance.” Instead, principles-based requirements are guidelines that FIs are expected to consider as they design and implement technology solutions. They are, by definition, subject to interpretation and can be prone to myths and misconceptions among FIs and their service providers. To illustrate this, let’s look at two aspects of DR that are frequently misunderstood within the Canadian financial services industry: data residency and geodiversity.
“My data has to stay in country X”
Data residency or data localization is a requirement for specific data-sets processed and stored in an IT system to remain within a specific jurisdiction (for example, a country). As discussed in our Policy Perspectives whitepaper, contrary to historical perspectives, data residency doesn’t provide better security. Most cyber-attacks are perpetrated remotely and attackers aren’t deterred by the physical location of their victims. In fact, data residency can run counter to an organization’s objectives for security and resilience. For example, data residency requirements can limit the options our customers have when choosing the AWS Region or Regions in which to run their production workloads. This is especially challenging for customers who want to use multiple Regions for backup and recovery purposes.
It’s common for FIs operating in Canada to assume that they’re required to keep their data—particularly customer data—in Canada. In reality, there’s very little from a statutory perspective that imposes such a constraint. None of the private sector privacy laws include data residency requirements, nor do any of the financial services regulatory guidelines. There are some place of records requirements in Canadian federal financial services legislation such as The Bank Act and The Insurance Companies Act, but these are relatively narrow in scope and apply primarily to corporate records. For most Canadian FIs, their requirements are more often a result of their own corporate policies or contractual obligations, not externally imposed by public policies or regulations.
“My data centers have to be X kilometers apart”
Geodiversity—short for geographic diversity—is the concept of maintaining a minimum distance between primary and backup data processing sites. Geodiversity is based on the principle that requiring a certain distance between data centers mitigates the risk of location-based disruptions such as natural disasters. The principle is still relevant in a cloud computing context, but is not the only consideration when it comes to planning for DR. The cloud allows FIs to define operational resilience requirements instead of limiting themselves to antiquated business continuity planning and DR concepts like physical data center implementation requirements. Legacy disaster recovery solutions and architectures, and lifting and shifting such DR strategies into the cloud, can diminish the potential benefits of using the cloud to improve operational resilience. Modernizing your information technology also means modernizing your organization’s approach to DR.
In the cloud, vast physical distance separation is an anti-pattern—it’s an arbitrary metric that does little to help organizations achieve availability and recovery objectives. At AWS, we design our global infrastructure so that there’s a meaningful distance between the Availability Zones (AZs) within an AWS Region to support high availability, but close enough to facilitate synchronous replication across those AZs (an AZ being a cluster of data centers). Figure 1 shows the relationship between Regions, AZs, and data centers.
Synchronous replication across multiple AZs enables you to minimize data loss (defined as the recovery point objective or RPO) and reduce the amount of time that workloads are unavailable (defined as the recovery time objective or RTO). However, the low latency required for synchronous replication becomes less achievable as the distance between data centers increases. Therefore, a geodiversity requirement that mandates a minimum distance between data centers that’s too far for synchronous replication might prohibit you from taking advantage of AWS’s multiple-AZ architecture. A multiple-AZ architecture can achieve RTOs and RPOs that aren’t possible with a simple geodiversity mitigation strategy. For more information, refer to the AWS whitepaper Disaster Recovery of Workloads on AWS: Recovery in the Cloud.
Again, it’s a common perception among Canadian FIs that the disaster recovery architecture for their production workloads must comply with specific geodiversity requirements. However, there are no statutory requirements applicable to FIs operating in Canada that mandate a minimum distance between data centers. Some FIs might have corporate policies or contractual obligations that impose geodiversity requirements, but for most FIs I’ve worked with, geodiversity is usually a recommended practice rather than a formal policy. Informal corporate guidelines can have some value, but they aren’t absolute rules and shouldn’t be treated the same as mandatory compliance requirements. Otherwise, you might be unintentionally restricting yourself from taking advantage of more effective risk management techniques.
“But if it is a compliance requirement, doesn’t that mean I have no choice?”
Both of the previous examples illustrate the importance of not only confirming your compliance requirements, but also recognizing the source of those requirements. It might be infeasible to obtain an exception to an externally-imposed obligation such as a regulatory requirement, but exceptions or even revisions to corporate policies aren’t out of the question if you can demonstrate that modern approaches provide equal or greater protection against a particular risk—for example, the high availability and rapid recoverability supported by a multiple-AZ architecture. Consider whether your compliance requirements provide for some level of flexibility in their application.
Also, because many of these requirements are principles-based, they might be subject to interpretation. You have to consider the specific language of the requirement in the context of the workload. For example, a data residency requirement might not explicitly prohibit you from storing a copy of the content in another country for backup and recovery purposes. For this reason, I recommend that you consult applicable specialists from your legal, privacy, and compliance teams to aid in the interpretation of compliance requirements. Once you understand the legal boundaries of your compliance requirements, AWS Solutions Architects and other financial services industry specialists such as myself can help you assess viable options to meet your needs.
Conclusion
In this first part of a two-part series, I provided some examples of common misconceptions FIs have about compliance requirements for disaster recovery in the cloud. The key is to avoid making assumptions that might impose greater constraints on your architecture than are necessary. In Part 2, I show you a structured approach for architecting compliant DR workloads that can help you to avoid these preventable missteps.
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