I am moving to Germany, and in the contract I signed I had to accept that all my data traffic can/will be checked by the apartment owner. The contract states:

Flatrate, aber hinter 30GB Tarif priorisiert, aslo etwas langsamer
Ja ich weiss, daß meine Daten überprüft werden.

Which translates to:

That after using an amount of 30GB data, the speed can/will be slower.

And the critical:

Yes, I know that my data is checked/investigated

Later in the contract one can read the following

Im Rahmen der gesetzlichen Bestimmungen (Anti-Terror-Gesetze und TKG) kann das Protokollieren der Daten erfolgen. Im Mietpreis ist eine FLAT-Rate enthalten, dabei können jedoch einzelne Ports gesperrt sein oder bestimmte Verbindungen mittels Traffic-Shapping bevorzugt oder verlangsamt werden. Bestimmte Geschwindigkeiten werden nicht zugesichert. Die Verbindung funktioniert nur, wenn DHCP eingeschaltet ist (z.B. bei Windows IP-adresse automatisch beziehen).

Which translates to:

In accordance with statutory requirements (anti-terror laws and TKG)
to log the data can take place. a FLAT rate is in the rental amount,
but it can individual ports to be blocked or certain compounds by
traffic Shapping preferred or slowed. Certain speeds are not
guaranteed. The connection works only if DHCP is enabled (eg
automatically when Windows IP address relate).

Since I really needed this apartment I was forced to accept this. But not anywhere does the contract says that I can not make it difficult for the landlord to check my traffic.
So my question is: would it be possible to make it difficult for the person watching my data traffic to see what I am actually doing on the internet? As you probably can tell, I do not know alot in this field.
Internet is provided via LAN, but I am going to use a D-link dir-635 router. And I am running Linux Mint.
I am not familiar with the prices of 4g/LTE in Germany, so I can not say if that is an option yet. I do not think I can get my own internet installed, and since the internet is provided in the rent (whether I want it to or not) it feels redundant to install a personal internet.

FINAL (hopefully) UPDATE: Well after all the very interesting and valuable discussion, it seems to me as though initial thoughts were correct. From the updated question, I would say that the restrictions are pretty standard for Germany.

My recommendation is that you ignore the noise and the concerns and simply make use of the service. Unless you have some very specific security needs that you haven't shared, using HTTPS wherever possible (which is best practice anyway) is sufficient. 

In any case, the other options discussed would all add overheads to your traffic which would use up your 30GB even sooner and slow things down.



There are several things you can do. Provided that the terms and conditions of use are OK with them.

You don't say what country you are in but you might want to get the terms of use checked by a lawyer since some terms may not be legally permissible anyway.

Here are four of the main ways you can protect your Internet traffic from the prying intermediate.


Make sure you always only connect to HTTPS sites

When you use HTTPS sites, the traffic is encrypted between you and the endpoint. Your landlords infrastructure will not be able to do more than examine the destination IP address, port and DNS. In particular, things like banking and health sites will remain secure.
Use a VPN

A VPN in this case is a 3rd party service that encrypts ALL of the traffic (not just web traffic as in 1) between your machine and the VPN host. This prevents any inspection of the traffic at all and it will appear as though you only talk to the VPN destination.

Unfortunately, it is possible that common VPN end-points might be blocked or even a smart security system used that will dynamically identify VPN traffic and ban it. Check the terms of use from your landlord carefully.
TOR

TOR is a way to obfuscate connections across the Internet and is often associated with "the dark web". However, it has legitimate uses as well. Unfortunately, it can add quite an overhead to traffic and may be unacceptably slow. Typically TOR will be used for web browsing, other network traffic would not be affected.
Use the Mobile network

If you are fortunate enough to live in an area with a) good (4G/LTE) mobile coverage and b) an affordable data tariff. Then using a 4G/LTE mobile router may be an option. You can get some staggeringly good data rates.

Don't expect to be free of restrictions though. Many tariffs don't allow device sharing, you'll need a special tariff for mobile data. You might not be allowed to use all services (like VPN's) and you are more likely to have national-level restrictions applied such as the UK's national "firewall".




It goes without saying (so I will say it anyway!) that you should ensure that you are staying within the letter of the laws of your locality & the legitimate terms of use of the landlords network. However, none of the above are illegal in most countries (well in most Western countries anyway) as long as you are not using them to do illegal activities. TOR and VPN's may possibly be illegal or at least get you unwelcome attention in certain countries.



UPDATE: Without question, the most security would be provided by a VPN. 

However, that will only be useful if the landlords network allows VPN traffic. In addition, VPN's also carry an overhead so things like real-time traffic (Skype voice/video for example) and online gaming would be impacted quite significantly.

In addition, VPN's will normally come at a cost though there are some discount codes around that might help.

It is possible to set up your own VPN if you have a server on the Internet to run it on. Most VPS hosts wont allow it but some will as long as you keep it private.

The real question is - do you really need to be bothered? That's why I mentioned HTTPS first. Since this protects your information to sites and since all decent online services already use HTTPS, you might find that this is a storm in a teacup.



UPDATE 2: As some others have pointed out. There are many flavours of VPN. A commercial service will be the easiest to consume but you need to do your homework to find the best for your region. Commercial VPN's can also be relatively easily blocked both by end point and by traffic inspection. Some VPN's require specific ports to be open on the network and these might not be available. Test before you buy. In general, those offering SSL-based or OpenVPN-based are likely to offer more options and be easier to get through any blocks.

Another form of VPN is to use an SSH client such as PUTTY (for Windows) connected to an SSH server (perhaps on your own or a friends VPS). You can throw in a local SOCKS proxy client and then you will have a very configurable private VPN service. Not especially easy to set up though if you don't understand the terminology. Note that many VPS services ban their use for even private VPNs.

Another thing to note is that there are several ways for security infrastructure to spot VPN traffic and therefore block it. Known end points for commercial services and known ports for VPN types are the easiest but it is possible to examine traffic patterns and work out that even apparent SSL traffic (e.g. if using port 443 for VPN) isn't actually.
