Multi-cloud connectivity tips: Transferring data between cloud regions
11 July, 2022 by Alex Hawkes
When it comes to multi-cloud, it’s easy to assume that the biggest connectivity challenge facing network professionals would be connecting between different cloud providers.
But actually moving data between different geographic instances of the same cloud platform is not as straightforward as you might think.
Being aware of data transfer costs between regions
Confusingly, all the cloud providers seem to have different approaches to cross-region data transfer and their own specific lexicon and definitions to go with it.
A common pitfall is that an organisation transferring a large amount of data from a public cloud environment in one region (Asia for example) to the same public cloud in another region (Western Europe for example), can be hit by hefty charges for traversing the cloud provider’s backbone between regions.
Furthermore, this often isn’t so easily solved by deploying dedicated connectivity to public cloud instances, because the network router will ‘think’ the data is staying within the one cloud instance and leave it be, when in reality it’s travelling across the world on the cloud provider’s native connectivity (as a chargeable transfer!).
Understanding this can be a headache, not least because the rules differ from provider to provider, but also because some data transfer types are charged only one-way (either in or out), while others have one fee when going in and another fee for outgoing transfers or between different zones or regions.
Let’s dig a bit deeper into the different approaches of the top three cloud providers…
Given its size and footprint, AWS has a more complex infrastructure than its closest competitors.
For AWS, a Region is a physical location around the world where it clusters data centres, and each group of logical data centres is an Availability Zone. However, each AWS Region consists of multiple, isolated, and physically separate Availability Zones within a geographic area, unlike other cloud providers, which often define a region as a single data centre.
AWS also goes one further with the concept of Local Zones, which place compute, storage, database, and other select services closer to end-users and are specifically designed for highly-demanding applications that require single digit millisecond latencies to end-users such as media & entertainment content creation, real-time gaming, electronic design automation, and machine learning.
Each AWS Local Zone is an extension of an AWS Region, providing a high-bandwidth, secure connection between local workloads and those running in the AWS Region.
For Google Cloud, regions are independent geographic areas that consist of zones. Typically, a Google Cloud Platform region will have three or more zones allocated to it, allowing organisations to distribute apps and storage across multiple zones to protect against service disruptions. These zones are physically located in the same or a nearby data centre.
Essentially, zones and regions are logical abstractions of underlying physical resources provided in one or more physical data centres. The data centres themselves may be owned and operated by the cloud provider, or they may be leased entirely or in-part from specialist third-party data centre operators.
However, the idea is still the same in that they are there to provide a uniform level of performance, security, and reliability. But, because zones or regions may exist in physically separate locations, perhaps even in a separate geography or country, relying on a cloud provider’s native connectivity to move data between instances can turn out to be costly for the reasons described above.
For Microsoft Azure, a region is a set of data centres, deployed within a latency-defined perimeter and connected through Azure’s own dedicated regional low-latency network.
An Azure geography is a segmented market containing one or more regions, that preserves data residency and compliance boundaries. This enables customers with specific data-residency and compliance needs to keep their data and applications in specific locations.
Azure Availability Zones are unique physical locations within an Azure region made up of one or more data centres equipped with independent power, cooling and networking.
Alternate ways to transfer data between cloud regions
There are ways to avoid backhauling your network traffic between data centre locations and the cloud - and even those cloud locations that are operated by the same provider.
Console Connect’s CloudRouter® is smart enough to take the burden off enterprises and avoid sending traffic over thecloud provider’s backbone, sending it over PCCW Global’s MPLS network instead.
What makes CloudRouter® different is that it creates a virtual ‘full mesh’ between network endpoints, ensuring that network traffic benefits from enhanced routing between data centre locations and the cloud.
Simply use the Console Connect centralised management portal to add or remove new network edge locations and let CloudRouter® do the rest.