Without rules governing the
exchange of data and establishment of connections between networks, there would
have a big chaos in the industry. These rules are called line protocols and are
very crucial for the inter-networking and communication across the networks.
The
mode and the speed of communication are controlled by what are called the
communications software packages. These network
protocols are defined by the international standards. However, having
international standards for the protocols has got both advantages and
disadvantages.
- A number of standard network protocols for carrying out
several functions such as routing, packetizing, and addressing and so on.
- All
these protocols lay out a standard definition of how the routing and addressing
has to be done.
- They also define the specifications for the structure of the
packets to be transferred between different hosts.
- Some commonly used routing
protocols are:
Ø X.25
Ø IPX/ SPX
Ø TCP/ IP
Ø OSI
- The OSI stands for open systems
interconnection.
- Early networking systems had a big problem which was that
there was a lack of consistency between the protocols employed by several types
of different computers.
- As a consequence of this problem, the international
standards came in to the picture.
- Thus, international standards were established
for the various data transmission protocols.
- For example, OSI is a set of
standard protocols developed by ISO (international standards organization).
- In
this model, the functionalities of the network protocols have been divided in
to seven layers of the communication rules or protocols.
- The purpose of this
model is to identify the functions being offered by the system.
- The following
three layers appear in the host systems and other units such as processor and
control unit etc.:
- Physical layer
- Data link layer
- Network layer
- The leftover layers are found in
the host systems only.
Advantages of having International Standards
Ø If all the systems are following
the same standard, it becomes easy for everyone to connection to everyone else.
In other words, the international standards provide easy interconnectivity.
Ø If any standard is widely used, it
gains economies of scale. For example, VLSI chips etc.
Ø With all the systems using the
same standard, the installation and the maintenance of the connections become
quite easy.
Ø Software designed by the
developers from all over the world, won’t have any problem in interfacing with
the host system and the other software. They will work well with a wide range
of operating systems and hardware since both are using the same standard.
Disadvantages of having International Standards
Ø Poor standards may be formed as a
result of the frequent standardization.
Ø Once the standard is adopted
internationally, it’ll be difficult to make changes to it. It will be difficult
to introduce new and better techniques in to it.
Ø If a problem occurs, it has to be
seen as an international problem.
Ø The manufacturers and companies
will be bound to follow the same international standards and so they won’t be
able to develop something better of their own.
Ø Large multinational companies
won’t be able to pool everyone in to using their proprietary protocols and
therefore no huge profits.
TCP/ IP protocol was developed to
make communication easy between the dissimilar systems. A number of hardware
and software vendors support this protocol ranging from mainframes to
microcomputers. A number of corporations, universities and govt. agencies are
making use of this protocol.
