[fulafel]

Mobile IP in IPv6 is very much meant to keep your stable, global address working while you roam around the global Internet.

The route optimization mechanism means your packets can travel directly between the mobile node's care-of address and the other guy if they both support MIP, so no need to be even on the same continent.

Sadly MIP is mostly dead, though there seems to be a somewhat up to date (2013) Linux impl of Mobile IP v6 and NEMO for IPv4 here: http://umip.org/

My impression is that it was kind of overshadowed by IETF's efforts to make an architecturally pretty fix to the whole locator-vs-ID thing. This is the work leading to the LISP protocol. You can now find papers from Facebook, Cisco, etc advocating its deployment. Hopefully it will get popular at some point.

[pyvpx]

those of us championing LISP are definitely working on it.