LAYERS IN THE OSI MODEL
The physical layer coordinates the functions
required to carry a bit stream over a physical
It deals with the mechanical and electrical
specifications of the interface and tr
To be transmitted, data must be
transformed to electromagnetic signals.
3.1 Analog and Digital
Analog and Digital Data
Analog and Digital Signals
Periodic and Aperiodic Signals
Signals can be analog or digital. Analog signals can have an infinite
Data Element vs. Signal Rate
For Analog Transmission,
S = (N 1/r) baud
Baud Rate Bit rate
Baud rate is number of signal elements per second
Bit rate is number of bits per second
Bit rate is the number of bits per second. Baud
Data can be either digital or analog.
Signals that represent data can also be digital or
We can represent digital data by using digital signals.
The conversion involves three techniques: line
TCP/IP PROTOCOL SUITE
The TCP/IP protocol suite was developed prior to
the OSI model.
Therefore, the layers in the TCP/IP protocol suite
do not exactly match those in the OSI model.
The original TCP/IP protocol suite was define