Analyzing Packet Switching Technique

A) Delay:

One of the main disadvantages of Packet switching is Packet Switching technique cannot be implemented in those applications that require low delay.

In packet switching mainly 4 types of delay occur:

1) Processing Delay: — This delay is mainly caused by time required to process a packet before sending or at any intermediate router or switch. This delay is generally very negligible.

2) Queueing Delay: — If large number of packets to be sent they have to spend some time waiting in a queue along the route. It depends upon the intensity and nature of traffic arriving at the queue.

3) Propagation Delay: — Time required to propagate one bit from source to destination. It depends upon the physical medium of the link. It is directly proportional to the distance between source and destination.

4) Transmission Delay: — It is the time required to place a packet on the link from the source. It depends upon the size of packet to be delivered.

B) Reliability:

Sometimes there a chance of losing any packet while transmitting data. But in case of packet switching if any packet is lost while transmitting, the destination end will itself detect it and then ask the source side to resend it. In this case it is more reliable than circuit switching. But for larger messages it generates more delay as compared to circuit switching. So, it is always preferred to send a data small in size by using this technique. In this case reliability is less for larger messages.

C) Data Transmission:

The packet switching technique transmits data through the network by breaking it down into several data packets for more efficient transfer. Packets are sent over a particular link depending on traffic present on a link. In this way all traffic gets divided and requires less time to reach destination. The above diagram depicts the data transmission in packet switching. The network devices direct or route the data packets to the destination where the receiving device then collects all of them and reassembles to get the proper orientation of the message.

D) Network Performance:

Packet Switching is an efficient technique. It does not require any established path for devices on a network prior to the transmission. Users can use the same communication channel simultaneously, hence makes use of available bandwidth very efficiently. If any of the path is busy between other two devices the same path can be used by a third device to establish network with another device. This one advantage makes network performance more efficient.

E) Implementation:

Packet switching is a method of transferring the data to a network in form of packets. In order to transfer the file fast and efficient manner over the network and minimize the transmission delay, the data is broken into small pieces of variable length, called Packet. Each packet consists of a header which contain IP address of source and destination, and a sequence number which is assigned to every packet while sending it. With the help of sequence number the packets are assembled properly at the destination. If the correct order of the packets is reached, then the acknowledgment message will be sent.

F) Error Handling:

If any error occurs while sending data from source to destination it is correctly handled by packet switching technique. Here if any packet loss in between due to some reasons, it gets detected at destination. As the message received is not complete, destination asks source to resend the complete message correctly. This is called as Retransmission of message.

G) Application:

• Newer mobile technologies such as ‘LTE’ uses packet switching.
• Applications like google chrome, skype, etc works on packet switching technique.
• While downloading a movie or a game from internet the data is divided in the form of small packets and these are coming to your PC by using packet switching technique.