Project Fi and the Great Firewall

Jared Geiger jared at
Sun Nov 15 03:08:49 UTC 2015

When you roam onto another cellular network other than your home network,
your data is encapsulated and sent back to your home network before going
out to the internet. This is to provide a seamless experience for the

The network it rides on is the GRX/IPX which is a a worldwide MPLS network
that the GSMA specified to make the data roaming experience work. The
GRX/IPX also can carry voice and text back to the home network. Since it is
a separate network from the Internet, the Great Firewall was bypassed.

There are several GRX/IPX providers and they all peer with each other in
key locations which usually end up being in the same major Internet peering
locations. TATA, Syniverse, SAP, Telia, and many others run an IPX/GRX
network and Equinix has IPX/GRX peering exchanges.

The wikipedia articles will start you in the right direction for more


On Sat, Nov 14, 2015 at 6:27 PM, Jake Mertel <
jake.mertel at> wrote:

> I know the service/device uses VPN if you are using "wifi assist" to
> connect to an open WAP -- it automatically tunnels the traffic so it can't
> be read by nearby snoopers. Perhaps they employ a similar technology or are
> using something like PPP to take all of the traffic back to one (or many)
> "access servers" before sending it off to the Internet. I have no
> experience whatsoever in cellular network operations, but I know many
> providers employ similar methodologies to assist in meeting their CALEA
> requirements.
> On Saturday, November 14, 2015, Roland Dobbins <rdobbins at> wrote:
> > On 15 Nov 2015, at 9:00, Sean Hunter wrote:
> >
> > While in China recently, I noticed that my Project Fi phone was accessing
> >> Google.
> >>
> >
> > Accessing, or attempting to access?
> >
> > Were you using a local SIM card, or roaming w/data?  What about WiFi?
> >
> > -----------------------------------
> > Roland Dobbins <rdobbins at>
> >
> --
> --
> Regards,
> Jake Mertel
> Ubiquity Hosting
> *Web: *
> *Phone (direct): *1-480-478-1510
> *Mail:* 5350 East High Street, Suite 300, Phoenix, AZ 85054

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