- Computer
Network Models
- Computer network model is
classified into two .These are OSI Model(Open System Interconnect model) and
Internet Model. We see each individuals in detials.
- OSI Model
- Open System Interconnect is
an open standard for all communication systems. OSI model is established by
International Standard Organization (ISO). This model has seven layers:
- Application Layer:
This layer is responsible for providing interface to the application
user.
- Presentation Layer:
This layer defines how data in the native format of remote host should be
presented in the native format of host.
- Session Layer: This layer
maintains sessions between remote hosts. For example, once user/password
authentication is done, the remote host maintains this session for a while and
does not ask for authentication again in that time span.
- Transport Layer: This layer
is responsible for end-to-end delivery between hosts.
- Network Layer: This
layer is responsible for address assignment and uniquely addressing hosts in a
network.
- Data Link Layer: This layer
is responsible for reading and writing data from and onto the line.
- Physical Layer: This layer
defines the hardware, cabling wiring, power output, pulse rate etc.
-
- Internet Model
- Internet uses TCP/IP protocol
suite, also known as Internet suite. This defines Internet Model which contains
four layered architecture. This model has the following layers:
- Application Layer:
This layer defines the protocol which enables user to interact with the
network.
- Transport Layer: This
layer defines how data should flow between hosts. Major protocol at this layer
is Transmission Control Protocol (TCP). This layer ensures data delivered
between hosts is in-order and is responsible for end-to-end delivery.
- Interne layer: Internet
Protocol (IP) works on this layer. This layer facilitates host addressing and
recognition. This layer defines routing.
- Data Link Layer: This layer
provides mechanism of sending and receiving actual data.
