Yes, an Ethernet cable can be connected to an S-bus. The RJ 45 plug fits exactly into an S-bus. However, like Wernerwitzeling, I don't see the point. The Ethernet cable only works for devices that understand the Ethernet protocol. Where can you still find an S-bus connection today?
I don't understand what an Ethernet cable with RJ45 connector and S-Bus (in model making???) should have to do with each other. Ethernet goes between devices that understand the Ethernet protocol (routers, computers, printers, etc.).