OSI Model Network Layer | Computer Networks Tutorial | Minigranth
Network Layer : OSI
Model
Network Layer is the
third layer from bottom of the
OSI Model and it is responsible for establishing data communication
channel between multiple networks or nodes or devices or
hosts.
It means, Network
Layer is held responsible for transportation of data packets between the
devices or nodes that are not locally connected to each
other.
Data is forwarded in
the form of data packets while using routing protocols to send these data
packets to their respective destinations.
Network-Layer is
required when a connection needs to establish between two or more different
networks. If two or more nodes or devices are connected or linked locally,
network layer is of no use.
Network-Layer
defines the most optimized and shortest path for delivery of data packets
from source address to destination address.
Network Layer :
Functions & Features
Network-Layer performs multiple functions and
have many features too. One of the major function is to en-route the data
packets from source to destination over different networks connected via
routers.
Logical addressing for all the devices present
across the network is given by Network Layer called as Internet Protocol(IP)
Address. It is a 32 Bit address which is unique for all the
devices.
Inter-Networking is another feature of the network layer. Whenever
there is a need to establish connection between two or more independent
networks, concept of Inter-Networking can be used.
Network Layer : Sample
Architecture
Multiple networks
connected through routers and data transmission in the form of data packets
is done, an optimized shortest path is chosen to transmit that from source
to destination called route and this process is called routing.
Quality of
Service(QoS) is another important feature which ensures that higher priority
based data packets are transmitted first rather than low priority data
packets. It is also responsible for error detection and
diagnostics.