[liberationtech] Verification of censorship resistance

[Philipp Winter]

On Fri, Nov 18, 2016 at 11:04:48AM -0500, Richard Brooks wrote:
> analysis. Does anyone have write ups on what national
> firewalls are using to filter traffic?
> 
> There are the obvious DNS names, IP addresses, port numbers
> and keywords in the traffic content.
> 
> What other header fields may be inspected?

<https://censorbib.nymity.ch/pdf/Marczak2015a.pdf>
<https://censorbib.nymity.ch/pdf/Ensafi2015b.pdf>

At least the Great Firewall of China is known to have used TLS headers
as distinguishers:
<https://trac.torproject.org/projects/tor/ticket/4744>