Technology companies need to provide the technology that will cumulatively make it too difficult for authorities to conduct mass surveillance, Edward Snowden told an audience of just a couple of dozen people watching his streamed Q&A session in a side booth at this year's by Southwest (SXSW) festival in Austin, Texas.

However, the full transcript and video clips of the event are available via Inside Live Blog and now reaching a wider audience so you can judge for yourself whether his explanations for his actions, and recommendations for action by the rest of us are valid.

Quizzed by ACLU's Chris Soghoian and Ben Wizner via a live Google Hangout – routed over several servers - with questions coming via both the live audience and Twitter, Snowden first promoted encryption, saying:

“The primary challenge that mass surveillance faces from any agency and any government in the world is not just how do you collect the communications as they cross the wires and find their way through the network, but how do you interpret them? How do you understand? How do you … analyse them?"

"There are two methods of encryption that are generally used. One is deeply problematic. One of those is … sort of what we are using with like Google-type services … right now … where I encrypt a video chat and I send it to Google. Google decrypts it and re-encrypts it to you guys.

"End to end encryption where it is from my computer directly to your computer makes mass surveillance impossible at the network level without a (key) … and (that method is) very expensive. By doing end-to-end encryption, you force … global passive adversaries to go for the end points … the computers. And the result of that is a constitutional, more-careful overseeing sort of intelligence-gathering model.

“This way, if they want to gather somebody's communications they have to target (one suspect's communications) specifically. They can't just target everybody all the time.”

But later in the discussion Snowden highlighted the limitations of this route, telling listeners:

“The bottom line I have repeated this again and again is that encryption does work. We need to think of encryption not as this sort of arcane black art … (but) as sort of a basic protection it is a defense against the dark arts for the digital realm. This is something we all need to be not only implementing but actively researching and improving on an academic level.”

When specifically asked for advice on improving personal privacy online, Snowden outlined some of the precautions he takes, from full disk encryption and network encryption (like SSL) to Ghostery for blocking ads and cookies and Tor for anonymous browsing.

“By using Tor you shift their focus to either attacking the Tor cloud itself which is incredible difficult, or to try to monitor the exits from Tor and the entrances to Tor and then try to figure out what fits. And it is very difficult."

Snowden did say that he wasn't leaking any new information, but he did comment that he would like to see enough public support to return home safely.