iPhone Tethering in PC: How Private and Secure it is?

First of all, you know that ATT doesn't permit this, right? Nor Apple.

So, you've jailbroken your phone to do this. Right off the bat, there's no assurance that ANYTHING about your iPhone is secure now. You might have downloaded malware, etc. and though that HAS happened through the App Store, Apple does make a serious effort to prevent it, and does pull apps when it is discovered.

Should really be no difference from a home DSL or cable connection in this regard. I don't think it's practical for anybody to "snoop" on your activity through the airwaves. The biggest point of vulnerability is the same as with a home Internet provider - the web sites you connect to (their policies, technology, and procedures), whether or not they use a secure (SSL) connection, etc. You should just read AT&T's policies for the last question, but wouldn't expect it's much different from other Internet Service Providers.

Quite a bit slower, and very high latency vs. a DSL or cable connection.

 

^^^^
He may just have a carrier hack and not be jailbroken.

 

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