Why a Router?

Router: With a router, you can create your own small computer network in your dorm room, where your devices usually go online via Wi-Fi through your router. Your router is connected to a device called a switch, which is typically located in the basement of your dorm. This switch is usually directly connected to us at Fichtenweg 5 in Tübingen via fiber optic cable. From there, the connection goes to the Data Center of the University of Tübingen, and from there to BelWü and beyond. The term Internet is based on the interconnectivity between networks.

To communicate between devices on the Internet, they need to find each other. For this, there are IP addresses, which we can compare to phone numbers for this explanation. We have a limited number of these addresses and can provide each of you with one. Since nowadays you have more than one device that wants to go online at the same time, it would cause problems without a router.

Access Point: An access point is not a router and does not create its own network. An access point is an entry point for a network. The access point needs an IP address to function. We give you exactly one IP address. If you connect an access point in your room, it gets an IP address from us. A smartphone connected to the access point does not go online at first, and you can’t access the access point because they don’t know each other’s addresses. The access point usually does not ask for a new IP address and forgets the assigned one after a while. A device in the Wi-Fi of the access point, such as a smartphone, continuously asks for an IP address and gets one from us after a maximum of two minutes if the access point has no more IP addresses. Then the smartphone can go online. Your laptop, however, will not go online through the access point. Therefore, you need a router.

Range Extender: Range extenders increase the range of a Wi-Fi network and do nothing else. So, you can’t do much with a range extender; at best, it might work like an access point.

Important Note: If you unplug your router and connect a laptop directly to the network socket, please wait 2 minutes before assuming there is an error or doing further diagnostics. The limitation to one IP address per room has a timer of 60 seconds. After 2 minutes, you will definitely have a new IP address from us if your devices are configured correctly.

Viktor-Renner-Strasse Update May 2024

We are resetting the settings on our hardware in Viktor-Renner-Straße to the original configurations by the end of the semester, so your devices should work as before.

This gives you the whole semester to replace any devices not allowed in our network (like access points and repeaters).

At the start of the winter semester, we will switch to our standard settings.

How Would I Choose a WiFi Router?

Finding the right WiFi router can still be a challenge for some. Let me walk you through how I would approach this as someone hypothetically moving in today, March 3, 2024.

I start by reading the guide on Netz-AK.de about Wireless internet in your room. This tells me exactly what features I need in a product:

  • WiFi Router
  • 5 GHz
  • Gigabit WiFi connection preferred
  • No Fritzbox, no D-LINK DIR-809

Next, I use a search engine to find a price comparing website for router in Germany. I find three German websites, which unfortunately tend to be exclusively in German: billiger.de, geizhals.de, and idealo.de. Knowing Geizhals, I start there.

On Geizhals.de, under the category Hardware > Netzwerk > WLAN-Router, I set the “Price range (€)” (“Preisbereich (€)”) generously up to 50€ including shipping. For availability (“Verfügbarkeit”), I select “in stock” (“lagernd”) and choose providers from Germany (“Anbieter aus Deutschland”). For the total 5GHz transmission rate (“Übertragungsrate 5GHz gesamt”), I select from 867Mbps to exclude outdated devices that only support 433Mbps. In the “additional filters” (“weiteren Filtern”), I find “WAN 1Gbit/s (exkl. Sets) ab:” and activate it. I then get results, which I sort by price including shipping, finding suitable routers from €27.99 including €5.99 for shipping.

To ensure the router I’ve chosen is compatible, I check it against the list on Netz-AK‘s site. If it’s not listed, I send the router’s name and, if possible, the product link via the contact form to receive a prompt reply about the device’s compatibility according to the manufacturer’s specifications.

I attempt the same at idealo.de but encounter difficulty as there appears to be no option to set a minimum WiFi speed or the minimum WiFi standard.

Lastly, I try billiger.de. Initially, I find no network technology category and almost give up after 5 minutes. Searching for “Router” eventually yields results. I also set the price limit to €50 here. Under product type (“Produkttyp”), I choose WiFi Router (“WLAN-Router”), for the WiFi data transfer rate (“Datenübertragungsrate WLAN”) I set the minimum to 866 Mb/s, and I use the LAN data transfer rate of 1000 Mb/s (“Datenübertragungsrate LAN”) as a proxy, though it doesn’t necessarily reflect WAN speed. This should suffice.

Now, I find suitable options here as well, unfortunately without shipping cost details. Where you decide to purchase is up to you, but personally, I don’t mind spending an extra €10 to shop locally. However, for a €30 router, an additional €10 is a significant 30% more, so don’t hesitate to return a product if local advice from a so-called specialist leads to a purchase that doesn’t meet your needs.

We will no longer support FritzBox routers

Starting from April 1, 2024, we will no longer support FritzBox routers in our network.

For a short while now, we’ve had all the permissions needed to tackle the ongoing issue with FritzBox routers.

We’ve been advising against using FritzBox routers for a while due to their cost and features that are unnecessary for a student dormitory setting. We’ve also linked to this advice in our guide since 2022.

Besides the wasted money, we’ve received complaints from various dorm areas saying, “when I’m away for a while and come back, I have to unplug and replug my router to get online.”

We were able to reproduce this issue widely when we upgraded a slightly neglected dormitory to Gigabit at the beginning of the year. During the upgrade, the dormitory also received Alcatel switches, which we’ve been exclusively using since 2012. With these switches, those with compatible routers could now enjoy Gigabit, but for those using FritzBox, the situation got worse.

Currently, it seems that FritzBox routers are the only ones unable to obtain an IP from our DHCP server a second time, eventually going offline.

We are conducting a small test setup to try and replicate this phenomenon observed in the wild, but it’s taking time.

We should invest in the next generation of switches, but that takes too long considering the short time residents stay in the dormitory, making it unreasonable to ask anyone to daily reset their FritzBox.

Therefore, we’ve decided to phase out FritzBox routers from our network by April 1, 2024, the start of the summer semester.

Those with older devices can receive a special configuration for their connection from us. Old devices are defined as: FritzBox routers that were in use in either of the two dormitories before their upgrade (Konrad-A-Str. and Viktor-R-Str.), i.e., the winter semester of 2023-2024.

In all other dorm areas, FritzBox routers haven’t worked for almost a decade, so we see no legitimate reason for complaints.

Anyone buying a FritzBox, despite our advice since 2022, will have to live with potentially needing to reconnect it daily. We will not invest our volunteer time into a special connection configuration just because someone chose to spend more money on a product we advise against.

When and how we will deploy our next generation of switches, which manufacturer they will be from, and whether FritzBox routers will work with them is not yet decided, and we ask that you refrain from inquiries about this.

Those interested in network technology are, of course, welcome to discuss and research this issue with us, but “I paid a lot of money and want my device to work” is not an argument here!

In short: from the summer semester of 2024, we will no longer support FritzBox routers in our network.

Maintenance Work Announcement week 3

In week 3, which is from January 15 to January 21, some maintenance work is scheduled.


The maintenance work starting on Friday will be long and unpleasant for the people in Hohenheim.
The fiber optic lines in Hohenheim to get extended to be used in a different location because of the renovations.
Without the fiber optic line, there will be no internet there.

The work will be carried out by a specialist company and is scheduled to start on Friday morning, which is January 19.
The work will take a long time, so we announce a complete internet outage in all student dormitories in Hohenheim from Friday morning to Saturday noon.

If it’s done faster, please avoid sending us messages all day. It won’t speed things up.
The company will complete their work as quickly as possible, and we will reconnect the fiber optics.

Tuebingen, Konrad-Adenauer-Strasse

On Thursday, January 18, starting around 5:30 PM, we will finally be able to equip our dormitories in Konrad-Adenauer-Strasse with modern technology.
For the residents, this means they will be able to use gigabit internet in their rooms afterwards.
Since we haven’t been able to implement the exclusive use of routers in Konrad-Adenauer-Strasse due to technical reasons, we will not enforce this immediately but only from the start of the summer semester (April 1, 2024).
We expect the installation to take about 3 hours, meaning you will probably have unrestricted internet access again from 9:00 PM.

Tuebingen, Schimpf-WG

There will be a maximum half-hour interruption in internet access at the Schimpf-WG. We had announced this work several times before but could never implement it due to problems accessing our hardware in the neighboring building. We cannot say exactly when this will be, but it will happen some evening between Monday and Thursday.

WiFi vs Internet

Sadly, we often hear the following two statements:

It can’t be the router settings because my Wi-Fi is working.


Here’s a photo of my working Wi-Fi connection, so my internet must be broken.

The root of the issue seems to be that people don’t understand the difference between Wi-Fi and internet access.

Here are three examples that could explain the difference to you.

Imagine your home is like a big library (which represents the internet). The librarian (your router) helps you find and borrow books (data). You and your family members can chat with the librarian using walkie-talkies (this is your Wi-Fi connection).

Now, even if the librarian’s walkie-talkie is working fine and you can talk to them (you have a Wi-Fi connection), the library might be closed or inaccessible (internet connection is down).

So, having a working walkie-talkie (Wi-Fi) doesn’t necessarily mean the library (internet) is open. The two are related, but different!


Imagine your Wi-Fi router is like a post office in your home. All your devices (like phones, laptops, and TVs) send and receive messages through this post office. Now, just because the post office is open (meaning your devices are connected to the router), it doesn’t necessarily mean it can send or receive mail to and from the outside world.

The Internet connection is like the trucks that come and go from the post office to other places. If there are no trucks coming in or going out (meaning no Internet connection), then your post office can’t actually send or receive any mail beyond your home. Your devices can still “talk” to each other within the home, like sending files or printing, but they can’t access anything from the wider world like websites or online games.


Having a Wi-Fi connection to a router is like being connected to the switchboard inside your house. You can talk to other devices in your home, like your smartphone talking to a smart TV. But that doesn’t mean the switchboard is connected to the outside world.

The router has another job: it needs to connect to the internet, which is like connecting your home switchboard to the big phone network outside. If that connection is missing or not working, you won’t be able to browse the web, watch online videos, or do anything else that needs the internet, even if you’re still connected to the router via Wi-Fi.

So, Wi-Fi connection to the router is just the first step. The router itself also needs to be connected to the internet for you to do most of the things you want to do online.

New in the dorm?!

Welcome to the dorm! It’s great you’re here.

If you’re wondering about the internet, don’t worry, it’s really easy! In your room, you’ll find a wall socket that gives you direct internet access. Prefer WiFi? No problem! You can easily set up your own WiFi router.

If you don’t have a router yet, you can get one for around 35 euros. We even have a list of routers that work well here. However, we don’t recommend any specific brand or model. Just a quick tip: FritzBoxes are not the best choice, and there’s really no need to spend more than 50 euros on a router.

If you ever run into a problem or need help, don’t hesitate to write to us using the contact form. Please always use this form so we get all the info we need to help you quickly and efficiently.

Have fun and enjoy your time in the dorm!

Your volunteers of the Netz-AK (short for Netzwerk Arbeitskreis = Network Work-group)

Speed test

We have set up an internal test for you some time ago. At netz-ak.de/speedtest, you can see how much your connection in your dorm room can handle.
We hope that all devices connected to our network via cable have a ping of less than 5 and an insignificant jitter.

A high jitter of over 5 indicates that the device from which you are measuring is connected via Wi-Fi and may be affected by what we call the 2.4 GHz problem.

Both download and upload should be just below the respective maximum of your building, i.e. 100 MBit/s or 1 GBit/s (1000 MBit/s). You can find out how fast the connections in your dormitory are under the expandable map on the  facts and figures page.

Currently, none of the dormitories are reaching the limit of their connection.

Why I wouldn’t buy a FritzBox for my dorm room

A FritzBox has a bundle of functions that are helpful for a family home or an office.

You don’t need the following functions:

  • VDSL modem
  • landline telephones, faxes, fancy door bells
  • mesh, repeater and power line functions

For all of that you are paying when you are buying a FritzBox.
That’s why they are more expensive that simple Wi-Fi router and do not improve your internet speed.

A simple router with 5 GHz Wifi costs about 35€, which is half the price of a used FritzBox 4040.

Setting up a simple Wi-Fi router is easier than setting up a FritzBox with all the functions you can and will not use in our dorm.

Dropouts in 2.4 GHz Wi-Fi

The reason why we do not recommend routers that do not create a 5 GHz Wi-Fi is very simple.
There are twelve channels in the 2.4 GHz frequency range, which means that theoretically a maximum of twelve such Wi-Fis can co-exist. In practice, a maximum of four 2.4 GHz Wi-Fis will work side by side without interfering with each other excessively.
2.4 GHz penetrates walls very well, but can transfer data less fast.
For dorm rooms a 2.4 GHz Wi-Fi is therefore very likely to suffer from interference and dropouts if you have more than four neighbors within a distance of 30 meters around you (even above and below you!).
A bad Wi-Fi okay for WhatsApp and surfing, but not for videoconferences.