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net4people / bbs

Forum for discussing Internet censorship circumvention
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I have my own VPN application, and I published it in the app markets. What is the difference between LTE and Home internet? #365

Open ffkaan opened 1 month ago

ffkaan commented 1 month ago

There are a lot of visits to the application from Iran and China, so I had the opportunity to talk to some users and the feedback they gave me was that it works on home internet but not on LTE. What is the difference between LTE and Home internet? How can I find out?

I use Openvpn, I have servers in 5 different providers, I can give more information if necessary.

wkrp commented 1 month ago

In general, censorship can be different on residential versus commerical versus mobile networks. But you will have to do some tests (or ask your users to do some tests) to discover what exactly is going wrong. A good first step is to try to determine at what point the connection fails: DNS lookup, TCP connection, TLS handshake, later in the connection.

Here are some references to different censorship in mobile networks in Iran:

https://github.com/net4people/bbs/issues/253

Iran has different types of censorship on different ISPs

In Iran, there are 2 most popular ISPs: MCI Hamrah Aval and MTN Irancell. These two are the most popular mobile careers and most of Iran's internet traffic is going through these 2 ISPs. There are other ISPs but these 2 have the strictest blocking out of all other ISPs. The GFW is different on MCI and MTN, for example, most of the IPs which are blocked on MCI work on MTN and vice versa, and also the proxy protocols that work on each one are different.

https://github.com/net4people/bbs/issues/231#issuecomment-1478274340

Some of my 4000 users are still blocked, but the block seems to be at the IP-level as I can't see their connection in my logs. Very few of my users get TLS handshake error, most of them are when using Mobile-data like 4G.

None of my users has problem connecting using a fixed line like ADSL.

https://github.com/net4people/bbs/issues/226#issuecomment-1485328614

It is reported that all ISPs route through AS49666, the Telecommunication Infrastructure Company, or TIC. This is consistent with what was reported in https://github.com/net4people/bbs/issues/188. (Note that TIC, the Telecommunication Infrastructure Company, is not the same as TCI, the Telecommunication Company of Iran, a major ISP.) TIC may be where centralized censorship is implemented. However, some ISPs, especially mobile ISPs, may implement their own layer of censorship before packets even get to TIC. As one commenter said, things like forbidden UDP packets get lost "too soon".

https://github.com/net4people/bbs/issues/182#issuecomment-1364080329

ISPs mostly act the same when it comes to censorship so there is basically two groups of them: home connections and mobile.

ffkaan commented 1 month ago

Hello, thank you for your answer.

From here, I can provide free VPN service to anyone who wants to test from the following countries. For China, Iran, Russia, India, we only have an iOS app for now, but we will release it on Android very soon. Telegram: [redacted]

wkrp commented 1 month ago

Thanks @ffkaan. I redacted the telegram channel name, since this is not a forum for end users, and it's not possible to check every link to ensure it's trustworthy. Discussion here is more oriented toward research and development. You are welcome to post about your VPN service, but we will want to see source code or technical design, in order to understand why it works and why it is safe.