Search Mailing List Archives

Limit search to: Subject & Body Subject Author
Sort by: Reverse Sort
Limit to: All This Week Last Week This Month Last Month
Select Date Range     through    

[liberationtech] Censorship circumvention and ticket inspectors

Michael Dahan dahanm at
Sat Jun 22 05:54:29 PDT 2013


I like this a lot and would like to use as an example for my students.
Perhaps using the Gaza Strip as a more concrete metaphor for some of the
ideas would be helpful... Certainly re SSH tunnels.

On Jun 22, 2013 3:41 PM, "Walid AL-SAQAF" <admin at> wrote:

> Dear friends,
> I have been asked to explain how four mechanisms of censorship
> circumvention work using some sort of analogy that any layman could
> understand. I proposed the analogy of surfing the Internet as traveling and
> firewalls as ticket inspectors checking where you are going as described
> below.
> So I would love to get from those of you who are familiar with censorship
> circumvention methods some feedback on how useful/accurate such an analogy
> is and ways to fix it. If you have another suggestion, I would love to know
> it because I could use it instead if it made more sense. This is all under
> development so changes can be accommodated.
> Note that I want the analogy to make it easier to  understand each
> circumvention method without implying something that is inaccurate when it
> comes to the limitations and abilities of each method.
> ==============
> Technology today offers a variety of Internet censorship circumvention
> solutions to bypass those ISP-imposed firewalls.
> To illustrate some ways of how Internet censorship could be circumvented.
> I don’t know about you, but I truly love to travel. So let me present this
> simple analogy of travel.
> *Using a particular website = Visiting to a particular town*
> *
> *
> *Protocol used (http, ftp, ssh, pop3, ....) = mode of transportation
> (taxi, bus, minibus, train, plane,..)
> *
> *Censorship authority (firewall) = Ticket inspector
> *
> And let us imagine that surfing the web, having a video chat or playing
> online games, etc. are all forms of travel. The different applications are
> like different transportation (e.g., train, car, sea, air).
> As a user in a country where there’s Internet censorship, you’re like a
> tourist hoping to buy a ticket to a particular destination as you can’t get
> out without having your ticket checked by the ticket inspector, who serves
> as the gatekeeper. Heavy censorship means very few destinations could be
> reached because tickets to forbidden destinations won’t be permitted by the
> ticket inspector.
> Now there are several methods of getting to a town that is normally off
> access.
> *Web-proxies: *
> If you get access to a web-based proxy, then it’s like having a ticket to
> an allowed destination that is not on the blocked list. However, that very
> destination is merely a transfer point where you could go to one more
> destination without any additional tickets. So while the ticket inspector
> thought you were going to a particular town, that town was basically used
> as a transfer point to another town that you were originally supposed not
> to go to. However, the ultimate destination could only be reached based on
> the conditions of the proxy station, which may not be convenient (too slow
> transportation, no air conditioning, etc., planting surveillance devices).
> But because the ticket inspector doesn't know, he let you go any way.
> Remember that this setting allowed you to only get one single ride. To go
> to another destination, you need to come back and take another ride.
> Surveillance is often possible to limit if the web-based proxy allows the
> use of SSL (adding an ‘s’ to http on the address bar).
> *HTTP/SOCKS proxies: *
> Through the HTTP/SOCKS proxy method, you’d get a pass that would allow you
> to go to one allowed destination and then from there, you would have free
> transfers on all the trains of the world. However, when you visit insecure
> websites (that don't start with https) with this method, you’ll sacrifice
> your privacy because you'll need to install a spyware device on your leg to
> track your movement for the ticket inspector to know where you are going.
> So when you come after a long vacation, authorities would know what you
> have been up to and what you bought and where you've been all this time .
> You might be in big trouble if you did naughty stuff while you were on the
> different trips.
> *SSH Tunnels:*
> Through a locally opened SSH tunnel, you would get a pass to an allowed
> destination that would grant you free access to not only trains, but also
> buses all over the world. At the same time, you also won’t be tracked. So
> you are really protecting yourself from being spied on while enjoying
> visiting almost all the destinations you wanted except the ones that can’t
> be reached by land.
> *VPNs: *
> And through VPNs, you show a pass to an allowed destination, from where
> you will be free to use all methods of transportation including land, sea
> and air. Furthermore, your movement or baggage would not be inspected. It’s
> the ultimate method that would allow you to be totally free in seeing the
> world with no restrictions.
> ==============
> Your feedback is welcome.
> Sincerely,
> Walid
> -----------------
> Walid Al-Saqaf
> Founder & Administrator
> alkasir for mapping and circumventing cyber censorship
> PGP:
> --
> Too many emails? Unsubscribe, change to digest, or change password by
> emailing moderator at companys at or changing your settings at
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <>

More information about the liberationtech mailing list