Google reported that the amount of encrypted online traffic hitting its servers jumped in the past year in a sign of heightened interest in protecting information on the Internet.

Google introduced a new encryption, or HTTPS, section in a transparency report released on Tuesday to highlight the need to safeguard data online.

Slightly more than 75 percent of requests to Google servers were encrypted as of January in a jump from 50 percent a year earlier, according to the transparency report.

"Implementing encryption is not easy work," Google "HTTPS evangelists" Rutledge Chin Feman and Tim Willis said in a blog post.

"But, as more people spend more of their time on the web, it's an increasingly essential element of online security."

The encryption section of the report was intended to provide a look at Google's efforts to encourage "everyone" to use the data-scrambling technology on the Internet, according to the post.

All messages sent using Google's free Gmail were encrypted, the report indicated.

Google is working to have encryption across all its online products and services. YouTube activity is not encrypted.

The vast majority of unencrypted traffic to Google servers come from mobile devices, many of which might never be updated by makers with improved security, according to the report.

Google shone a spotlight on encryption less a week before Apple and the US government are to face off in federal court in Southern California in a legal fight to force the company to break into an attacker's iPhone.

Apple on Tuesday filed a written response brief saying the tactic would have appalled the country's founders.

Apple stuck to its argument that the FBI was overstepping legal bounds by using an All Writs Act to compel the company to help break into an iPhone used by one of the shooters in the December terror attack in San Bernardino, California.

Apple sees the request as a demand for a "back door" into software powering all iPhones.

The government brief, in sharp contrast, argued it is a single case of making a "modest" demand for technical assistance in an important national security investigation.

An FBI victory in the case could serve as a legal precedent backing requests for access to iPhones by law enforcement agencies throughout the US.