Project Fi and the Great Firewall

Sun Nov 15 04:02:53 UTC 2015

My team mate was traveling to China with his Nexus 6 (with Project Fi
SIM-card) and was able to access Google services. The phone uses roaming
data to access Google and your phone gets IP assigned by your home mobile
network packet gateway (P-GW). There is no local data break-out.

On Sat, Nov 14, 2015 at 6:00 PM, Sean Hunter <jamesb2147 at gmail.com> wrote:

> Hello everyone,
>
> I come to you to humbly request your assistance, on or off list. This not
> an urgent technical matter, but something I'm rather fascinated by at the
> moment.
>
> While in China recently, I noticed that my Project Fi phone was accessing
> Google. Not only Google, but Facebook, YouTube, Gmail, Twitter, and many
> other normally perma-blocked websites. It's taken me a few days of sleep
> deprived thinking to realize this, but I'm seeing the same or similar
> 26.x.x.x addresses across countries I've visited, including China, Spain,
> Malaysia, and Hong Kong.
>
> I'm not a cellular guy and I know even less about MVNO's, but I'm curious
> if I'm inferring the technical operations of the network correctly. It
> sounds like the local cellular companies are provisioning access upon
> arrival, then packing up the packets and shipping them off at layer 2 or
> below to Google, who's then handling the IP stack and up internet access.
> I'm also assuming the Great Firewall then acts above these layers since
> it's not blocking access on my phone.
>
> If my inference is correct, I'd be curious to see if those responsible for
> the Great Firewall are aware of this deal Google has with a Chinese
> cellular provider and the technical specifics of how it works. Might we be
> seeing a softening of Great Firewall policies for foreigners, or just
> another soon to be inspected or blocked flow of traffic?
>
> Anyway, I'd just love to hear from a knowledgeable engineer about how this
> works.
>
> If you've read this far, thanks for your time and have a great day!
>

-- 
Best regards,
Yury.