First layer of the OSI model covers the cabling and electrical signaling. The first layer of OSI model is the physical layer. The physical layer also decides the transmission mode and physical media.
physical layer
The top most layer is the application layer and bottom most layer is the physical layer. Since data is transferred from top to bottom, I would say that the starting layer is the application layer.
1. Physical layer
physical layer
Layer 1 - the physical layer
physical layer
Interfaces used on the system to connect to Network devices reside on Physical layer.
physical layer
Physical layer
The physical layer of the OSI model is responsible for encoding frames in to the electronic/RF/optical signals of the physical medium and for reading the media and translating back in to usable frames.
none of protocols include a physical layer specification