What is the name of this cable hanging between the sockets now?

In our new building, the router was originally supposed to be placed in the hallway, and for that purpose, these connections were installed; see attachment. When I wanted to connect the router, I was told: "That won't work like this. There is no fiber optic here." So the router was placed in the utility room at the telephone socket. From there, a cable runs to the hallway. Currently, this "monkey swing" is between the router and the office. We can switch it between the router and the living room. I would like to have a second cable so that both the office and the living room have LAN. The electrician does not know if he still has such a cable. What is it called? Then I could try to get it.

Is a patch cable. So a simple network cable.

It's a patch cable. So, a simple network cable.

You should be able to find that in any electronics store, right?

The electrician doesn't know if he still has such a cable.

That hurts!

Yes, you can probably find something like that at MediaMarkt or similar stores. However, a switch is missing, with which you can "split" the signals. Although that looks like duplex - it should work without it. You just need 2 cables. An additional "monkey swing" and then the other side again to the router.

It's interesting how the network requirements in this forum differ by miles.

The curious thing is that until now only one cable was connected to the router, which was labeled Büro. In the hallway, the monkey swing was plugged in at Wohnzimmer. Although the cable labeled Wohnzimmer in the utility room was not connected to the router – probably due to the lack of a corresponding connector – there was internet on the TV in the living room. Now I just switched the plugs around in the hallway, I have LAN in the office, but not on the TV anymore. As a layman, I would think that the orange Wohnzimmer cable in the utility room also needs to be connected to the router. What is this cable called?

The orange cable is presumably an installation network cable, intended for laying within the house. A keystone module was attached to it to connect a patch cable.