Physical layer in ISO OSI Model

Physical layer in ISO OSI Model

 

Functions of Physical layer in ISO OSI Model


 Physical layer deals with electrical , mechanical , functional and procedural characteristics interface and media.

  1. Representation of bits.

  2. Synchronization of bits.

  3. Topological specification.

            physical layer is responsible for selecting the appropriate topology. ( bus, ring,mesh, star,tree )


  4. Type of link.

            Point to Point.
            Broadcast.

  5. Define transmission mode.

           Simplex : Here data can be transmitted only in one direction.
                         eg. keyboard, CPU to monitor.

            Half Duplex : Here data can be transmitted in both directions but not simultaneously.
                          eg. Walkytalky.

            Full Duplex :Here data can be transmitted in both directions simultaneously.
                           eg. telephone cable. computer cable.