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Does anyone have any stats on this?

I'm mainly asking from a private network perspective (assuming that they are affected by the firewall as well). That is, all of my apps that are in use in China are on our internal network.

I got to thinking about this after reading Mr Denny's recent answer on SQL replication. Now I'm wondering how much of a hit my app is taking in China because of the firewall.

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Are you asking about Youth Escort Green Dam, or the national infrastructure firewall? – kmarsh Sep 28 '09 at 21:49
I'd be far more concerned about what kind of latency their firewall creates on freedom of information, buuuuut that's a topic for another day – Mark Henderson Sep 28 '09 at 21:50
up vote 1 down vote accepted

When I was working on it, we calculated round trip at 550ms, with about 250ms of the time being native network lag time, about about 300-350ms of time being spent on the firewall.

This was over a T1 with no traffic on it (it was dedicated to SQL Replication traffic).

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Uuuuugggh...... – squillman Sep 29 '09 at 1:08
Bah, in Australia a < 500ms ping to anywhere is not bad, < 200 is awesome and < 100 is unheard of. You get used to it. – Mark Henderson Sep 29 '09 at 1:40
Ouch. That's brutal. Guess there's not a lot of high traffic stuff going in or out of Australia without some major pain. – mrdenny Sep 30 '09 at 0:49

Bruce Schneier commented on an article about how the firewall works and how to circumvent it. Warranted, the article is from 2006, so things might have changed, but it's a worthwhile read nonetheless.

Besides the closed TCP connections, I'm not aware of any other practices that the Chinese use with their firewall, so connections shouldn't incur too much more of a penalty. The added latency of connections to China are more likely due too the distance traveled than the firewall.

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