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(Corrects name of VPN to Hotspot Shield, not Hotshot Shield)
By Evren Ballim and Paul Sandle
ISTANBUL/LONDON, June 5 (Reuters) - Turks are turning toencryption software to thwart any ramp up in censorship of theInternet after six days of anti-government demonstrations and awave of arrests reportedly for urging people to protest onsocial media sites.
Hotspot Shield, a VPN (virtual private network) thatdisguises users' identities and encrypts traffic on the Web,said more than 120,000 people had signed up to its service inTurkey since the weekend, more than 10 times typical levels.
The software has been used in recent years by democracymovements around the world, including in the Arab Spring, tocircumvent government censorship of social media services suchas Facebook and Twitter, said David Gorodyansky, founderof Hotspot Shield creator AnchorFree.
Authorities in Egypt, Libya and Syria attempted to closedown Internet access completely to quell protests.
Gorodyansky said authorities had not blocked access inTurkey, but they had "throttled down" speeds, making the sitesunusable for periods of time.
Police raided 38 addresses in the western port city of Izmirand detained 25 people on suspicion of stirring insurrection onsocial media with comments on the protest, opposition CHP partydeputy Alaattin Yuksel told Reuters on Wednesday.
Izmir Deputy Prosecutor Ali Haydar confirmed that adetention order was issued for 38 people, but declined to giveinformation on charges or how many were detained.
Before the arrests, protesters in Istanbul had voicedsuspicions that the Internet was being restricted.
"We had problems accessing Twitter and Facebook Saturdaywhen the protests were intense," said Deniz Utku, a digitalmarketing agency founder whose office is close to Taksim Square,the centre of the demonstrations.
"I used VPN to access social media for 1.5-2 hours. I don'tthink this (slowness) was caused by the high demand ... Wecouldn't open the pages without VPN."
The government has made clear its disapproval of socialmedia services, which are being used more and more as newspapersand television come increasingly under the sway of the state.
In a television interview last week, Prime Minister TayyipErdogan described sites such as Twitter as a "scourge", sayingthey were used to spread lies about the government with the aimof terrorising society.
Regulators and operators, however, said no sites had beenblocked. "No restrictions have been made in accessing socialmedia sites," Tayfun Acarer, head of the telecommunicationregulator Information and Communication Technologies Authority(ICTA), told Reuters.
Turkcell, the country's leading operator, said ithad not received any request to block mobile communications inany part of Turkey. "Our technical teams are working to provideuninterrupted communications services as always," the companysaid on Twitter.
Industry experts said thousands of protesters in Istanbulwould have put a heavy strain on networks.
Vodafone, a British company that was criticised whenit complied with government demands to switch off service inEgypt along with other operators in 2011, said it had increasedcapacity in Turkey to meet demand for social media, inparticular for sending images and video over mobiles.
Turks have also turned to other smartphones apps that can beused to maintain communications in case of a clampdown, such asZello, which allows an iPhone to function like a walkie-talkie.It is currently a top-ranking app, according to App Annieanalytics.
"The really interesting thing here is that tens of thousandsof people are downloading Hotspot Shield and other communicationapps in anticipation of further censorship," said AnchorFree'sGorodyansky.
"It just goes to show how evolving internet and mobile apptechnology is helping to thwart attempts to limit democraticrights and freedoms." (Additional reporting by Ozge Ozbilgin from Ankara; Editing byWill Waterman)
