Is a TAE socket no longer needed?

Addition: To be honest, I don't even know if the house has a cable connection. The previous owners had television via [SAT], internet via [DSL Telekom].

The wiring is the same in both versions, i.e. I tell the all-rounder to lay duplex LAN cables from the basement to every living room and install double RJ45 sockets there.

okay, but then the installation must be done the same way in both cases, right?

"Behind" the FritzBox it is the same, the model of the FritzBox (usually rented together with the tariff) differs between Telekom/Vodafone (telephone cable) and Kabel Deutschland (broadcast cable). With Telekom, they will offer you T-Entertain Triple Play. It is important for the electrician that the cables are terminated with 8P8C and that the socket is suitable for this (RJ45 is a broad term, including some "ISDN" sockets that are wired 8P4C). I would choose separate cables – gluing the two cables together brings no advantage.

And when moving in, I will decide on one of the two options. Right?

Correct. The switch in the basement still needs power. The access points as well, preferably via a switch with PoE.

It is important for the electrician that the cables are terminated with 8P8C and that the socket is suitable for this (RJ45 refers to a broad spectrum, including some "ISDN" sockets which are terminated with 8P4C). I would choose separate cables - taping the two cables together brings no advantage.

All right, thanks! According to Vodafone information, the cable would be available; I hadn't even thought about that option. The description of this socket says: "Shielded Cat.6A network outlet with two RJ45 (8/8) connectors for data transmission rates up to 10 Gbit Ethernet according to IEEE 802.3an." That should fit then, I think.

so I tell the all-rounder to lay duplex LAN cables from the basement to every living room and install double RJ45 sockets there

I would approach the matter with a bit more planning.

- Basement: Should the patch panel, switch, and other devices be nailed to the wall or should everything go into a network cabinet?
- Living rooms: A double socket per room is already quite good, but TV or office might need more. This way, an additional socket in the room can be avoided.
- Access Points: Of course, these can be connected to a regular network socket or a special place can be provided, e.g., high up on a wall or on the ceiling. With POE, no power outlet needs to be nearby, but these APs are rather something from the enterprise sector. You should have at least one access point per floor. Position depends on the floor plan.
- Cable routing: The best solution is to lay the network cables in a conduit so they can be replaced. Because nothing is more future-proof than a sufficiently dimensioned empty conduit.
- Patch panel: Always choose a few ports larger than the number of cables arriving. Over time, you tend to install more.
- Adjacent rooms: Besides the living rooms, hobby rooms or the garage should not be forgotten when supplying the network.
- WLAN in the garden: If this is desired, at least prepare for it, because it is not always guaranteed that the WLAN from the house also reaches the garden.

Thank you very much for the hints. I had considered the garden; a LAN socket is quite well positioned there. All cables will also be laid in empty conduits. Network cabinet: in the old basement it can of course sometimes get damp, maybe a good idea.

Or then (because of possible moisture in the basement) better to put all devices (patch panel, switch, router) in the utility room on the ground floor? And if so: what should the wiring look like, is that more complex?