Microsoft has taken a strong stand against the National Security Agency (NSA), which has been embroiled in spying controversy.

The software giant has acknowledged that its customers have "serious concerns about government surveillance of the Internet" and, therefore, it is taking steps to ensure that governments adopt a legal process rather than "technological brute force" to gain access to customer data.

"We are especially alarmed by recent allegations in the press of a broader and concerted effort by some governments to circumvent online security measures - and in our view, legal processes and protections - in order to surreptitiously collect private customer data," wrote Microsoft's general counsel Bradford L. Smith in a blog post.

The Redmond-based company calls any government efforts to spy on its online communications an "advanced persistent threat."

To thwart online data snooping by the government, Microsoft is set to add encryption technology, dubbed Perfect Forward Secrecy, to tackle spying. Google, Facebook and Yahoo have also promised to do the same. 

Additionally, Microsoft said it will also scramble the links between its data centers, which will give assurance to users and foreign governments that the data is not freely accessible to the NSA.

The Perfect Forward Secrecy setting will become default for users by end 2014.

Smith said the company had considered such action for a while now, but the recent NSA spying jolted it into action.

"The idea that the government may be hacking into corporate data centers was a bit like an earthquake, sending shock waves across the tech sector," said Smith. "We concluded that we better assume that there might be such an attempt at Microsoft, or has already been."

"For many years, we've used encryption in our products and services to protect our customers from online criminals and hackers. While we have no direct evidence that customer data has been breached by unauthorized government access, we don't want to take any chances and are addressing this issue head on. Therefore, we will pursue a comprehensive engineering effort to strengthen the encryption of customer data across our networks and services," he added.