In the battle for top cloud billing, Microsoft, Google and Amazon Web Services have all had a busy few days.

Firstly Microsoft has been showing a great deal of love towards Linux by including Red Hat Enterprise Linux images in the Azure Marketplace for the first time. Microsoft has also made the Azure Container Service broadly available, certified Bitnami images for the Azure Marketplace, and introduced OneOps support on Azure.

Corey Sanders, director of program management, Azure said: "Both Microsoft and I love Linux, and just days after Valentine’s Day, I am ecstatic to showcase this love with several new announcements."

Red Hat Enterprise Linux now being available in the Azure Marketplace means that Microsoft is moving more towards open source and Red Hat. This makes sense for the company as 60% of the images on the Azure cloud are Linux.

Essentially what this boils down to is a big play to have a cloud that is more open and flexible.

Microsoft isn’t alone in this, however, with Google’s Cloud Platform being given a more flexible unit of cloud computing capacity.

The new flexibility comes in the form of Custom Machine Types, which allow the buyer to configure computing power with different amounts of processing power and memory, allowing users to choose the best fit for the application.

Typically users are billed by the hour for AWS EC2 or by the minute for Google and Microsoft.

The Custom Machine Types breaks this down even further so that users can build the type of computing they need by adding or subtracting memory to the compute node as needed.

Custom Machine Types first came out in test mode in November but they have now entered general availability.

The context of this is that customers may well prefer to have exact billing for precisely what they used, so it is billing at a fine granular level. For a small business this might not make a huge amount of difference, but for large enterprises it might do.

Google has been trying to push more into the enterprise market as it looks to catch up with AWS, which started its own push around five years ago, while Microsoft already had a footing in the market.

The search and ad giant’s move into the enterprise cloud market has been highlighted by the hiring of Diane Greene to head up the Google Enterprise business. Greene, a co-founder of VMware, brought experience of working with enterprise customers.

Never one to be slow with the updates or to be left behind by its competitors, AWS also recently made improves to the security features in Lambda and the Relational Database Service.

Added features include the ability to encrypt Elastic Block Store boot volumes and giving customers greater control over encryption keys for the AWS Key Management System.

The added security features play to improving the image of public cloud services for being as safe as or safer than on-premise deployments – again it is about appealing to the large enterprises.

AWS Lambda is the other offering to get an upgrade with Lambda VPC support, this allows for encrypting shared snapshots in the Relational Database Service, other changes include the ability to encrypt existing databases within RDS, support for Lambda to access resources behind a Virtual Private Cloud and a custom authentication to API Gateway through Lambda function.

This was initially pitched in October at its re:Invent conference in Vegas, but has just now become available.