With Wi-Fi calling it gets a bit more simplified (no "transit" operators in user plane) and may provide better privacy (only your home country will monitor your calls, lol). The UE establishes IPsec tunnel over the Internet to the home operator and uses it for native VoIP/messaging applications.
On Sun, Nov 15, 2015 at 9:33 PM, Carlos Alcantar <car...@race.com> wrote: > > Similar to the SS7 phone network where call signaling data is done on a > totally different path then the actual rtp path. > > > Carlos Alcantar > Race Communications / Race Team Member > 1325 Howard Ave. #604, Burlingame, CA. 94010 > Phone: +1 415 376 3314 / car...@race.com / http://www.race.com > > > ________________________________________ > From: NANOG <nanog-boun...@nanog.org> on behalf of Jared Geiger < > ja...@compuwizz.net> > Sent: Saturday, November 14, 2015 7:08 PM > To: NANOG > Subject: Re: Project Fi and the Great Firewall > > 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 > customer. > > 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 > information: > https://en.wikipedia.org/wiki/GPRS_roaming_exchange > https://en.wikipedia.org/wiki/IP_exchange > > ~Jared > > On Sat, Nov 14, 2015 at 6:27 PM, Jake Mertel < > jake.mer...@ubiquityhosting.com> 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 <rdobb...@arbor.net> > 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? > > > > -- Best regards, Yury.
