Virtual network interface

[Petr Pisar]

On 2014-11-07, Vít Ondruch <vondruch at redhat.com> wrote:
> Is there way how to setup some virtual network inteface, which would
> always work, no matter if I use ethernet, wireles, VPN or whatever else
> network connection on background?
>
Your question contains the answer: You need to create a tunnel to an
always reachable node and use the tunneled IP address. This way you will
have always a static IP address on your mobile host.

There are other posibilities like mobile IP extension or multipath TCP
or even some experiments splitting node's IP address into location and
identifier halves. (In order of number of deployments :)

> * It is pretty annoying that every time I change my location, I have to
> change configuration of my virtual machines, just because now I am not
> connected via ethernet, but via WiFi.

You assign your own private addresses to them and use them in scope of
your host and virtual machines running in it.

> * I don't understand why my Xchat should loose connection, when I am
> switching from ethernet to WiFi (and they are both available during
> interim period).
>
The reason is that processes usually work with transport adresses (e.g.
a TCP) and these include network address (e.g. an IP). And network
addresses in the current Internet are used as locators, thus they
depend on the network topology.

> The type of network connection is just implementation detail, so why
> this does not work? If there is possible to create some virtual network
> interface, which would take all the real network connection under one
> umbrella, this should be default for Fedora Workstation.
>
Well, it is possible. But any site operator would shot you because you
would break his precious one-way firewall.

-- Petr