Hi Luca, Please see below.
On Tue, Dec 23, 2014 at 10:45 PM, Luca Stornaiuolo < [email protected]> wrote: > In truth I'm studing the state-of-the-art of multihoming in Android. > Some years ago, in Finland, I worked on HIP. It was promising but now it > seems deserted. Then -in Android- SCTP, but for some reasons I'm interested > in non-root scenarii only, so LISP. > My professor asked me to extend something of LISPmob, so the obvious ways > seemed two: or multiple EIDs support (which may be considered as an > implementation for the *end-host multihoming*); or enabling multiple > interfaces with the same EID (*end-site multihoming*). > Obviously, the second topic was more interesting, but -as far as I knew > until this evening- again impossible without rooting... > Actually both scenarios are supported in LISPmob, fully on the Linux version and partially on Android. As of today, what you can do in LISPmob for Android (non-root) is to have a single EID associated with several physical interfaces in an active-backup fashion (i.e. you can use one physical interface or another at a given point). What you can't do in non-root Android (at this point) is to have more than one EID or use several physical interfaces simultaneously (i.e. use two or more physical interfaces at the same time). A common use-case that we have tested several times is to run LISPmob non-root in an Android device in order to be able to keep the same IP address (the EID) while seamless roaming from WIFI to 3G (or the other way around) without loosing established connections. Something that we'd like to have, but that we have lacked the time to look into, it's to support several physical interfaces at the same time (i.e. send traffic through WIFI and 3G simultaneously). That would allow for nice traffic balancing, offloading and bandwidth aggregation on Android devices. > Hence I've tried the other way, but with the same bad results. > > Nevertheless, I just read this on VpnService.Builder.estabilish()... > "[...] it is rare but not impossible to have two interfaces while > performing a seamless handover. In this case, the old interface will be > deactivated when the new one is created successfully". > > So, it *is* possibile to configure two interfaces (each one with its own > EID) for the same VPN just with these APIs! Or do I misunderstand it? > If I understand the API docs right, you'll be able to have two different VPN interfaces at the same time, but only one will be operative (i.e. the outcoming traffic will only be forward to one). You can keep accessing the older one (to get leftover packets), but you can't send traffic through it. In other words, you can't send traffic through two different VPN interfaces at the same time. As I told you, if you want to have different VPN interfaces to support multiple EIDs at the same time, you'll probably have to hack Android code. I don't know how hard that would be or if it is even feasible. > > Sorry for bothering you, in general and so close to Christmas, but since > LISP is still quite new in Italy, I'm very interested in it [image: 😏] > No problem at all :) Best, Alberto > > Luca > >
