Computer Networks:

Physical Layers
Data link Layer(DLL)

Network Layer

Transport Layer:

Session and Presentation Layer:

Application Layer:

 
☚ OSI Model
Transmission Technique ☛

Network Layer

Network layer is the third layer of the OSI  (open system interconnection) model is delivery of data package from the source to the destination through multiple nodes.
From the transport layer it received in form of Segment and add header file (source and destination address) in Network Layer and capsulate it Called Packets, and then deliver the packet to the data Link Layer so that the data link Layer further send to receiver side at the destination and the packet is extended and deliver to the corresponding transport layer. it also control the operation of the subnet.

Network Layer

Function of Network Layer 

  • Network Layer carry the data packet from the source to the destination without changing or using them.
  • If the data  packets are too large for delivery they are fregmented into small pices called packets.
  • It decide the roots to be taken by the package tour travel from the source to destination.
  • The source and destination address are Added here.

Services offered by Network Layer

  1. Packetizing
  2. Routing
  3. Forwarding.

Packetizing:

the process of encapsulating the data receive from the upper layer (Transport Layer) of the network, In network layer Data are encapsulating the payload and at the destination data are decapsulating the payload is known as Packetizing.


At the source end the data are encapsulated by adding a header file that contain the source and the destination address and some other relevant information required by the network layer protocol and deliver the packet to the data link layer.

At destination the packets are receives, the network layer packet from its data link layer and Decapsulated the packet and deliver further to the corresponding upper layer i.e transport layer. the routers in the path are not allowed to change either the source or the destination address and also not allowed to decapsulate the packet.


Routing :

Routing is the process of moving data from one Device to another device, in

network layer there are numbers of routes available, network layer specify some strategies which finds out to be the best route.

Network Layer

Forwarding:

Forwarding is a simply define as the action applied by each router when a packet arrives at one of its router node. when a router receives a packet from one of its attach network (node) its needs to forward the packet to another attach network(node) or to some attention router. router are used in this network for forwarding a packet from the Local Network to a remote network.

In this the process of moving data from one device to another device it’s operate on the network layer are working on the bases of forwarding table

 

Routing:
  • Routing is the process of moving data from one device to another device.
  • Router are used in this network .
  • Working on the based on forwarding Table.
Forwarding:
  • Forwarding is simply define as action applied by each node when a packet is arrived .
  • it worked on the network layer.
  • check the forwarding table and works according to that..

Services provide by the network layer:

  • Guaranteed delivery:

 network layer guarantees that the packet will arrived at its destination.

  • Guaranteed delivery with bounded delay:

this service guarantees that the packet will be delivered with a specific hope to host delay bound.

  • In order packets:

This service ensures that the packet arrived at the destination in the order which they are sent it.

  • Security service:

the network layer provide security by using a session key between the source and the destination hos

☚ OSI Model
Transmission Technique ☛

Computer Networks:

Physical Layers
Data link Layer(DLL)

Network Layer

Transport Layer:

Session and Presentation Layer:

Application Layer: