The DSL cable is plugged into the grey DSL connection of the DSL router and the other side of the cable with the TAE plug is plugged into the middle TAE socket. Normally, a so-called DSL signature cable is used for this purpose. Since the device you mentioned is not designed for use in Germany, you will have to get a suitable cable yourself. 

You mean that adaptor:

Is that correct?

Then, how was previous tenant connected via distiribution box by RJ45?

The TAE adaptor is not suitable as it may lack the circuit for the galvanic signature:
https://telekomhilft.telekom.de/t5/Geraete-Zubehoer/Signaturkabel/ta-p/2065992

The Ethernet connection for Ethernet wall outlets in the house installation is made via the yellow Ethernet sockets of the DSL router. This is LAN, not WAN.

Hello @mmpes ,

welcome to the o2 Community .

You’ve already some good information from blablup concerning your setup and how you can connect your router to the internet. If anything should come up before or after the activation, please let us know.

Kind regards, Sven

Hello which annex mode do you operate for DSL configuration? Annex A or Annex B?

Thanks

For ADSL2+ connections Annex-J is used, for VDSL2 connections up to 100 Mbit/s profile 17a, for VDSL2 connections up to 250 Mbit/s profile 35b. 
Please note that PPPoE with VLAN-ID=7 is required in each case. 

See also DSL interface description TR112.

Are these settings correct? Thank you for your effort and help. I appreciate it.

And according to the 1TR112_V14.pdf file you sent, in section 7, It is said that “The transmission mode "VDSL2" according to o7], Annex B is used.” Is that correct?

I am not familiar with this device and its settings. If you have questions about the operation or settings of your device, contact its manufacturer. 
Annex B/J is correct. Annex A was never used in Germany. 

Moin,

try

Than

Could you share your modem's “Administration- DSL Setting” @schluej  Thanks in advance

That’s not my router. Reset the router and start the setup Assistent with Telekom.

If you get ask for Username than enter the Username with the @ sign and the Passwort.

Hello @mmpes ,

I’m looking forward to hear from you after the activation tomorrow, and hope that everything will work out smoothly and that you can go online then.

Kind regards, Sven

Hello again.

At the time being, I am writing this message using my O2 DSL internet connection.

First, thank you @blablup for your great help and the correct information you gave in separate messages.

Second, thank you @schluej for the images. It helps me verify my settings.

Third, it is important and great to see you follow these messages to help @o2_Sven.

Lastly, I would like to summarise the required information to connect your DSL line via a modem bought from a different country. It may help other customers:

1. Be careful about your TAE-F RJ11 cable for connecting your modem. Use proper cable according to the messages above.
2. I use 50 Mbit DSL connection. So,  the profile 17a and  Annex B/J is correct, also PPPoE with VLAN-ID=7 is required.
3. Please see the attached WAN - Internet Connection settings for ASUS:

   

    

4. Please see the attached DSL settings for ASUS:

   

    

5. Please see the attached picture of my current DSL logs, is there any problem, @o2_Sven and @blablup ?

   

    

As an additional information, you reach out ASUS Germany-spesific modem/router settings are here (from the manufacturer).

Hello @mmpes ,

thank you for your posts and the information. I’m sure these will be helpful for someone in the future if they need to setup another ASUS device.

Kind regards, Sven