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Since many of you already know the Iranian government aggressively uses internet censorship to block sites such as facebook, flicker, bbc, etc.

The Iranian people use various methods to bypass filtering like VPN (l2tp,pptp,ipsec) openvpn protocol, HTTPS, socks5, HTTP , kerio vpn ...

since the day before yesterday everytime i connect to ANY of those services it connects with no problem but loose the connection less than a minute!

my first question is how do they do it? second and more important, is there any other protocol left for us?

read more:

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I have obfuscated-openssh server running on one of my boxes, and I give tunneling access to friends people in China, Iran, Syria, and other countries. As I'm writing this, I can see that 2 people from Iran are connecting (one of them for at least 3 hours). So I guess that can be your last resort. – Adi May 6 '13 at 21:00
On a different note, I know for sure that this behavior is seen in China (connection reset). So one would assume that your government has recently adopted the same methods. – Adi May 6 '13 at 21:03
Tor with Obfsproxy might still work. – CodesInChaos May 6 '13 at 21:25
@CodesInChaos Yup, I can confirm that is currently working in Iran as well. – Adi May 6 '13 at 21:38
As of this morning, obfuscated-openssh isn't working anymore in Iran. – Adi May 7 '13 at 12:04

It's hard to tell for sure what they are doing, but they may be doing something as simple as cutting off any connection they don't understand that is leaving the country. If that's the case, then you would basically be out of luck.

If they are doing something more elaborate, it unfortunately wouldn't be possible to know what they are doing without a fair bit of digging and trial and error as I doubt they publish their exact methods of trying to censor.

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Actually, cutting off makes great sense. You detect dissenters and do not leave them enough bandwidth to communicate effectively... – Deer Hunter May 6 '13 at 20:59
I wouldn't do too much digging though, especially if an oppressive govm't is watching. – Polynomial May 7 '13 at 10:11

I haven't tried this, but it looks reasonably practical... If you are someone outside Iran, and you want to help your relatives, set up a VPN on your computer and give the permissions to your friends inside Iran.

Setting up a VPN is not hard. see these :

This way, if any of us, give access to 3 or 4 people, a big portion of them will have free internet access.

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A possible solution must be direct uplink/downlink satellite connection to bypass this kind of restrictions. You have some satellites who have footprint in your area.

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This could be one of the worst piece of advice to give to someone in a country like Iran. This will most likely get the guy arrested. First accusation would be "Utilizing high tech communication devices to communicate with America and Israel". Please weigh your words before typing them. – Adi May 7 '13 at 11:06
@Adnan But proxies wouldn't get them arrested? – Luc May 7 '13 at 11:41
@Luc Come to The DMZ, your sarcastic/rhetorical comment would take a lot to reply to. – Adi May 7 '13 at 11:49

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