Originally Posted by docbert

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However, once you're on public open internet it's a different story - for two reasons. Firstly, there's the issue of do you trust the provider? How trustworthy is your local coffee shop, or the free wifi you happened to find at the train station?

But even if you do trust the provider, there's the second question of how you know if you're actually connected to that provider. I do generally trust Comcast, so if I see their "xfinitywifi" network I potentially trust it also - but how do I know that it's really xfinitywifi, and not someone simply pretending to be them? Same with Starbucks wifi, or your airports free wifi. If it's an open network, you generally can't trust it as you don't know who's really behind it.
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