Types of delay: 

1. Transmission Delay: Transmission delay is referred to as the time taken to put the data packet onto the outgoing transmission link. Transmission delay depends on the length/size of the packet(L) and bandwidth of the network(B) and is calculated as :

Transmission Delay(Tt) = Data size/bandwidth = (L/B) second

2. Propagation Delay: The time it takes for the last bit of a data packet to pass across the medium and reach the other end is known as propagation delay. The propagation delay is determined by the distance (D) between the transmitter and receiver, as well as the wave signal’s propagation speed (S). It’s calculated as follows:

 Propagation Delay( Tp )= Distance / Velocity=(D/S)second 

3. Queuing Delay: When a data packet arrives at its destination, it must queue before being processed. Queuing delay is the amount of time a data packet spends waiting in a queue before being processed. There is no set formula for calculating queuing delay; it is determined by the rate at which incoming packets arrive, the outgoing link’s transmission capacity, and the nature of the network’s traffic. 

4. Processing Delay: The amount of time it takes processors to process the packet header is known as processing delay. The processing of packets helps in detecting errors and deciding where to route the packet. It doesn’t have a formula because it is determined by the processor’s speed.