Are LAN sockets still up-to-date? WLAN/wireless is the future!

Whether double or single sockets, I will still decide depending on the room.

The main thing is that you address the double sockets like two single sockets: so as a double with two corresponding cables. Think about the use with two devices in different VLANs and possibly also mixed, one with and one without PoE.

Telephone sockets are, as I have learned, outdated. Is DECT the only option left??

Telephone sockets in the sense of ISDN or just telephone/telefax are outdated. Ecumenical telephone sockets for voice and non-voice data terminals are called network sockets. Not cabling is outdated, but the separation of ITK into IT and incompatible TK as in the imperial era (when ERGO was still Hamburg Mannheimer).

In my opinion, Cisco produces inexpensive IP phones with Ethernet connection instead of TAE. However, these are wired office devices.

That sounds a bit misleading, as if TAE were just another plug type. So, a landline phone can also come in the form of an IP-DECT/cat.iq phone connected to the network socket. That means: into the socket — into an outlet with PoE — goes a cordless IP phone with its own DECT/cat.iq base station. From the Fritzbox’s perspective, this is an IP device, since the handset is addressed by its own base. The base is in this sense an access point for one or more handsets, regardless of whether they additionally have their own charging cradles. And I would put them in a voice VLAN. For example, the Gigaset DX800 can also address mobile phones as handsets — if only grandmothers really use the landline, dedicated cordless landline phones hardly pay off. Personally, I always also have a corded phone at my desk (e.g., the mentioned Gigaset).

For the access point, a network socket? I thought I’d just let the cable stick out of the wall/ceiling and then connect the access point via PoE?!?

I don’t understand the question: first, why shouldn’t the access point be plugged in, and second, what does PoE have to do with whether it is plugged or hardwired?

I don't understand the question: firstly, why shouldn't the access point be connected via a plug, and secondly, what does PoE have to do with whether it is plugged in or hardwired?

I misunderstood it the first time. My question is now resolved. I understood it.

The main thing is that you also address the double sockets like two single sockets: so as a double with accordingly two cables.

Yes.

One more quick question. Depending on what the electrician understands by the telephone connection mentioned in the construction description, this will be omitted. I could still have these work carried out, but then have empty conduits laid instead of telephone cables. That should only involve a few additional costs at most. At least similar work would have to be done anyway according to the construction description. Or am I misunderstanding something?

No, you understand that correctly. In principle, he would have to lay the telephone cable in the installation conduit anyway. Therefore, there should be no additional costs if you have the work done but leave out the telephone cable and the socket.

No, you understand that correctly. In principle, he would have to lay the telephone cable in the installation conduit anyway. So there should be no additional costs if you have the work done but omit the telephone cable and the socket.

That is good to know. Of course, it could be that a conduit with a larger diameter might be needed. But the work itself is the same. So that I can argue properly.

In the end, you should even get money back since cables, sockets, and installation are not required...