[tor-talk] p2p(skype and other VOIP) blocked in .UZ [translated]

Marcin Cieslak saper at saper.info
Mon Sep 14 07:59:50 UTC 2015


On Mon, 14 Sep 2015, Vladimir Teplouhov wrote:

> Hello.
> 
>   У кого-нить уже есть информация по блокировкам интернета в Узбекистане(и др.)?
> Что там применяют или испытывают?

[translated from Russian, with apologies to both Russian speakers and
English readers]

Hello,

Does anybody have any information about Internet blocking in Uzbekistan (and others)?
Are they experimenting with something there?

Skype and other voice services have ceased to work...

http://uforum.uz/showthread.php?t=15221&page=205

what is known at the moment:

* Gernally a high-speed transmission is experienced between Uzbekistan
and Russia, one gets initially a working voice and video connection, but
after few seconds the voice connectivity stops working. Chat
continues to work...

* VPNs used to relieve the situation, but later VPN networks ceased
to work (according to rumors TOR is not working
as well, but I haven't verified that yet).

* One can observe that connections are filtered in transit between
Russia and Uzebkistan, a purely domestic traffic seems to work 
properly (but I think they may expand the filtering activity also to
cover internal connectivity as well).

* The government and ISP officials pass the buck towards Russia - 
therefore one cannot rule out some recent work done in Russia
and the use of Russian equipment.  A financing for projects concerning
for example TOR detection and blocking has been announced on the Russian
government procurement portals. (A provider has a financial interest
in blocking VoIP services of the competition, _as this brings
a revenue increase for telephony_ - that's why providers
do have a vested interest here; but nevertheless the use of 
Russian equipment cannot be excluded [even in this case]).

Initially I thought they identify VoIP users by traffic
volume, which is seems pretty easy, but _the connectivity
is not blocked completely_ (as it would be in case an IP
address is banned), and the chat is working...

There are also issues popping out with adding new
contacts on Skype!

That's why I started to suspect, that a more advanced methods
are used, possibly they analyze and crack network procotols,
including p2p - which is unexpected and very dangerous.

Vladimir

PS according to some rumours the provider purchased some expensive
equipment in China, but I think that development of the filters
is most probably by somebody else (in .UZ there are simply no
experts and no money, I don't think that they have more far-reaching
goals than just blocking some anti-government sites, but the equipment
being used apparently can do much than that!)...

Apparently the peripheries of the Internet serve now as a testing
ground for the new blocking technology, so we can expect that
similar issues will pop up in Russia and other countries, as well
as in the homeland of the NSA - USA... What do people think about
this?

PPS if the block size of the bitcoin protocol will be expanded
it will become visible to a crude [volume-based] traffic analysis,
even without analysis of the protocol itself... (in general
I think we should start considering building of [new] *physical*
connectivity channels independent of the government and
consider construction of the new Internet, independent of
the governments...)

So right now there is a good possibility to work out and
test countermeasures - but we should not wait any longer,
as the experience shows "the problem is solved" by turning
off the filters for certain periods of the day and
re-applying them again in the most unexpected moment.

PPPS please translate this into English - automated
translations usually give not only a rough translation,
but they also distort the intended meaning.


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