Can you guess which tech companies have the best chance of keeping the National Security Agency (NSA) from spying and keep your data protected against interception?

Google, Dropbox, SpiderOak and Sonic.net are the only web-based companies that met all the five communications encryption steps that are recommended by a survey from the Electronic Frontier Foundation (EFF), a digital rights advocacy group.

After the recent revelations of surveillance by the NSA of Internet users, EFF surveyed major web companies to find out which ones were using encryption to protect their data center transmissions, users' emails and online activities.

"We've asked the companies in our Who Has Your Back Program what they are doing to bolster encryption in light of the NSA's unlawful surveillance of your communications. We're pleased to see that four companies-Dropbox, Google, SpiderOak and Sonic.net-are implementing five out of five of our best practices for encryption," says EFF.

Apart from Google, Dropbox, SpiderOak and Sonic.net, Twitter and Yahoo also intend to encrypt data transmissions between center.

"In addition, we appreciate that Yahoo! just announced several measures it plans to take to increase encryption, including the very critical encryption of data center links, and that Twitter has confirmed that it has encryption of data center links in progress," notes EFF.

Additionally, Facebook and Tumblr have told EFF that they too intends on encrypting data links between computer centers.

"Facebook and Tumblr have provided further information to supplement the Encrypt the Web Report. We're pleased to report that Tumblr is planning to upgrade its web connections to HTTPS this year and implement HSTS by 2014, and Facebook is working on encrypting data center links and implementing STARTTLS," per EFF.

EFF has therefore given them a five out of five.

"In light of the National Security Agency's unlawful surveillance programs, as well as other threats to network security, it is now more important than ever to deploy strong encryption throughout networks," said Kurt Opsahl, EFF Senior Staff Attorney, in a statement.