internet architecturee evolved out of experiences with an earlier packet
switched network called the ARPANET. Both the Internet and the ARPANET wer e
funded by the Advanced Research Projects Agency (ARPA).
Internet and ARPANET were around before the OSI architecture, and the
experience gained from building them was a major influence on the OSI reference
model. Instead of having seven layers, a four layer model is often used in Internet.
lowest level are a wide variety of network protocols, denoted NET1, NET2 and so
on. The second layer consists of a single protocol the Internet Protocol IP. It
supports the interconnection of multiple networking technologies into a single,
layer contains two main protocols the Transmission Control Protocol (TCP) and
User Datagram Protocol (UDP). TCP provides a reliable byte stream channel, and
UDP provides unreliable datagram delivery channel. They are called as end to
end protocol they can also be referred as transport protocols.
above the transport layer, a range of application protocols such as FTP, TFTP,
Telnet, and SMTP that enable the interoperation of popular applications.
must be able to transfer data from one device to another with complete
accuracy. Some part of a message will be altered in transit than that the
entire content will arrive intact. Many factors like line noise can alter or
wipe out one or more bits of a given data unit. This is known as errors.
TYPES OF ERRORS
There are two types. They are, 1. Single Bit Error
that only one bit of a given data unit is changed from 1 to 0 or from 0 to 1.
2. Burst Bit Error
that two or more bits in the data unit have changed.
o A burst
bit does not necessarily means that the errors occur in consecutive
o The length of the bust error is measured from the first corrupted bit to
the last corrupted
bit. Some bits in between may not be corrupted.