Please remove my email address and identifying headers if forwarded to

A number of large research-oriented universities in the U.S. have
recently become targets of filtering policies being implemented by
China ISPs. There has been limited discussion of these recent events,
but Jonathan Zittrain and Benjamin Edelman's very informative page have
identified that these filters have been put in place.  What hasn't been
widely discussed is the collateral damage being done by these filters.

It appears that select and specific IP addresses of authoratative DNS
servers operated by a few of the major research-oriented univerisities
are now being filtered.  This policy has the obvious effect of
preventing users in China, who are behind these filters, from being able
to resolve DNS names from those select university DNS servers.  This in
turn denies access to hosts universities are authoritative for when
accessed by name.

This action has the, probably unintentional, result of filtering traffic
in the other direction.  Many of these university DNS servers are the
same ones used for recursive queries by the university's client hosts.
Since the filters are blocking university DNS server IP addresses,
university DNS servers can't get packets through to China for the
purpose of doing a lookup on China host names.  The result is
effectively no access from China to select universities and no access
from select universities to China.

There are some relatively simple methods for universities to get their
lookups resolved, but the specific details about the techniques used by
China ISPs and the university countermeasures I'm purposely being vague
with or leaving out, but it is not difficult for those who understand
the technical details of Internet operation to guess what goes on and
what sorts of things this ends up leading to.

Putting aside all the political arguments, I expect this sort of
censorship warfare and its countermeaures will continue to become more
prevalent, more complex and more annoying for those using and operating
certain parts of the Internet. If these activities are unique to U.S.
universities I'd be surprised. If they are, they probably won't be for

I am a member of one large U.S. research-oriented university and have
first-hand knowledge of this issue.

------------------------------------- You are subscribed as [EMAIL PROTECTED] To manage your subscription, go to http://v2.listbox.com/member/?listname=ip

Archives at: http://www.interesting-people.org/archives/interesting-people/

Reply via email to