The Physical Layer defines the means of transmitting raw bits rather than logical data packets over a physical link connecting network nodes. The bit stream may be grouped into code words or symbols and converted to a physical signal that is transmitted over a hardware transmission medium. The Physical Layer provides an electrical, mechanical, and procedural interface to the transmission medium. The shapes and properties of the electrical connectors, the frequencies to broadcast on, the modulation scheme to use and similar low-level parameters, are specified here.
Within the semantics of the OSI network architecture, the Physical Layer translates logical communications requests from the Data Link Layer into hardware-specific operations to affect transmission or reception of electronic signals.
no tranmission is suitated below physical layer that is we can say on layer 0.
Modems Transmission media connectors Repeaters
The physical layer is the lowest layer of the OSI Network Model. It is the part that physically transfers data from one location to another location. For instance, in your cell phone, it is the physical radio that encodes, transmits, and decodes your data packets. In a carrier pigeon network, it would be the carrier pigeons and their pigeon roosts.
That is considered part of layer 2.That is considered part of layer 2.That is considered part of layer 2.That is considered part of layer 2.
A PHY chip takes a set of data, and turns it into a string of bits to allow the data to be transmitted across a physical medium, such as fiber optic cables. This is part of Layer 1 of the OSI model.
A PHY chip takes a set of data, and turns it into a string of bits to allow the data to be transmitted across a physical medium, such as fiber optic cables. This is part of Layer 1 of the OSI model.
outer core
The Physical layer is responsible for the actual hardware connection. The physical addressing is handled by the Data Link Layer.
lower mantle. Or
The MAC sublayer is part of Layer 2 - Data Link Layer - but it is more correct to say that the MAC address is the physical address.
A hub is a layer 1 (physical) device because it does not use any part of the packet header to direct the packet to the right destination, it just broadcasts to all connected computers.
The ozone layer is a part of another layer within it. The name of the layer is Stratosphere in atmosphere.
This Layer Is The Lithosphere