"Tor has been fighting this arms race with the Chinese for years -- it's very difficult."
Clive Robinson suggested in comments that there may be a more serious issue. "It may be a move designed to perform espionage by trying to force company secrets out into the open," he wrote. "Forcing companies off of VPNs ... will in effect open up corporate firewalls, thus also aiding in APT type activities."
Schneier said he doesn't know the intent of the government, noting, "That's more a political science question than a computer security question."
But if multiple international companies decide they can't risk losing their private, internal information, that could ultimately harm the Chinese economy. Astrill, the VPN provider, told its users it hopes the crackdown will be lifted.
"We believe [the] China censorship minister is a smart man ... and this blockage will be removed and things will go back to normal," it said in its email to users.
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