Computer Networks Lecture 9

Difference between OSI and TCP/IP Layer

OSI	TCP IP
7 Layers	5 Layers
PDU Unit Protocol Data Unit	Segment
There is no port number, IP address Socket, Physical Address	Socket, Port, IP Address
Single Transport	UDP TCP Protocol
Less Security	IPSEC, HTTPS
Network Byte Order
Little Big Endian
Functions related for Conversion

HTONL unsigned Long Integer to network Byte Order
HTONS Unsigned Short to NBO S = Short 16 bit
HTHL an unsigned Network Byte Order Long Integer to Host Byte Order L = Long bit 32 Bit
NTOHS An Unsigned short NBO to host byte order

Error detection with hamming and parity checks

Study the figure and recognize the link

Fast ethernet → atm → sonet → fast ethernet

Functions of datalink layer

References