How to deal with Dual-Stack Lite and incoming connections

Question

My ISP (german cable ISP Unitymedia) forced me to use DS-Lite / Dual Stack Lite because he ran out of IPv4 addresses.

Common problems with that setup are:

• interrupted connections (i.e. in online games)
• problems to access your local network via any IPv4 address
• even problems accessing the local network via IPv6 (IPv4 pref
• home automation not possible

Are there ways to overcome the limits of this interim solution? I would like to achieve the following use cases:

1. Host my own OwnCloud server for personal data and sync with my mobile
2. Connect to the internet via a VPN connection from my Android device for Hotspots
3. Connect to OSX/Windows machines via RDP or VNC (possibly from an IPv4 environment)
4. Stream music from my library to my mobile device
5. Allow non-tech-savvy users the same access
6. Use other services like SSH... from an IPv4 endpoint

Some ideas:

• A portmapping service that routes all the traffic through their servers > not really an option because not sure about data safety and it costs money.
• A Tunnel broker maybe?
• A local server that automagically keeps open a connection to an IPv4 device
• Something like AutoSSH with a reverse tunnel but for other services...
• A similar solution like Skype or Bittorrent uses to punch through firewalls.

Possible similar discussions I found, but without a real world solution are:

• How to prove provider is blocking incoming traffic on some ports?
• 4in6 tunneling (via OpenVPN?)
• Does IPv4 and IPv6 talk to each other?

Any ideas for a cost-free, relatively simple solution/workaround?

(I must say I have a hard time understanding IPv6, tunnel brokerage, NATing, package encapsulation and all that.)

Solution

Let me go through them one by one:

Host my own OwnCloud server for personal data and sync with my mobile

You can't have incoming connections through the DS-Lite NAT box, so: only over IPv6, not over IPv4

Connect to the internet via a VPN connection from my Android device for Hotspots

Same: only over IPv6, not over IPv4

Connect to OSX/Windows machines via RDP or VNC (possibly from an IPv4 environment)

From an IPv4-only environment: no

Stream music from my library to my mobile device

If your library can connect out from your LAN to your mobile device: yes. If your mobile device also can't accept incoming connections (because it is also behind a NAT): only over IPv6, not over IPv4

Allow non-tech-savvy users the same access

Only if they have IPv6, then it is easy. You have plenty of public IPv6 addresses, so you can create hostnames in DNS for them. Over IPv4: no

Use other services like SSH... from an IPv4 endpoint

And again the same: sorry...

IPv4 and IPv6 are separate protocols. IPv4 has reached the end of its (comfortable) lifetime. See what Vint Cerf (one of the inventors of IPv4) has to say about it from 14:00 onwards. The only real solution is to start using IPv6. And to push those providers and services that don't support it yet.

Finding someone to give you an IPv4-over-IPv6 tunnel from the internet to your LAN will be difficult. I have a small company that offers LISP based services for such use cases (not trying to advertise here, just trying to show possibilities), but you were specifically asking for a cost-free solution. IPv4 addresses are scarce: finding someone who offers you such addresses (and the bandwidth to use them) for free will be (almost) impossible.

Comments

[Admin]

I'm René the head of the feste-ip.net team you are linking. In your mention about data security i would like to add the comment that theoretically any Hop in your connection path from your workstation to a target can be used to record your traffic. So it's not really a higher privacy risk using our services. Always select encrypted transports like https / ssh and there is no disadvantages using our portmapper.

[sir_brickalot]

Thank you. But I was aware of the fact that there is no direct communication between v4 and v6. I thought more of a "translation" service similar to the portmapping service or some idea how to keep connections open (like AutoSSH+reverse tunnel) for some or better all of the goals.

[Sander Steffann]

There are solutions for NAT between IPv4 and IPv6, but you often run into problems with the MTU. For TCP you could rent a server with a public IPv4 address, which then proxies incoming connections to your IPv6 addresses. Not very efficient, and not cost-free, but possible.