Data is transferred from the source to the destination in a network. Sometimes the data is transferred in bulk in the network which affects the traffic. Now, if the traffic gets more and more in the network, therefore increasing the congestion. This leads to delay in data receiving or sending packet loss, and blocking of the connection resulting in the capacity of the network.
Network Congestion:- Network protocols are there which help in reducing the network traffic, by taking the SHORTEST PATH ALGORITHM which says that, the data is routed by seeing the shortest path of the desired destination. The data packet which creates congestion will be destroyed by the protocol services, this will lead to data loss(though it makes the channel overcome the congestion). Now, seeing this problem one more facility was introduced, of providing ACKNOWLEDGMENT (ACK). If the data is received by the destination then it will make an ACKNOWLEDGMENT (ACK) to the sender (that he has received the data). The same if not received by the destination, will not give any ACKNOWLEDGMENT (ACK). This will ensure avoid redundancy(duplicates of data), and again the data will be sent by the sender. This will help in reducing congestion and also data duplication. Thus retransmission of the data compensates for the lost packet.
Traffic Congestion:- Traffic congestion is a condition on any network, in which traffic of the sending and receiving data increases and is followed by slower speeds, longer trip times, and increased queuing. The most common example is the physical use of roads by vehicles. When traffic demand is great enough then the interaction between vehicles slows the speed of the traffic stream, and congestion occurs. As demand approaches the capacity of the network, extreme traffic congestion sets in. When packets of data are fully stopped for periods of time, this is known as a traffic jam as we have seen on roads. The same problem is solved by the SHORTEST PATH ALGORITHM.
WHEN DOES THE CONGESTION ARISES?
1. Capacity – It is the capacity of the network to bear the maximum traffic. Bottle Necks (networking terminology) are created due to the traffic, when the network does not attain its limit of traffic then it is called BOTTLE NECK.
2.Traffic Incidents:- It is that process in which the traffic effects the normal data flow in network.
3. Traffic Control Techniques :– Algorithms are made so that the traffic is controlled in a better way. Like earlier discussed about the Shortest Path Algorithm, is used to make the congestion under control.
4. Fluctuations in Normal Traffic :–Daily you have a different packet of data to send, of variable bytes, if the data is very bulky then the data will be received by the destination after a little delay.
The delayed data is waste for the destination, so congestion should be avoided.