PACKET SWITCHING

DEFINATION :-

Packet Switching transmits data across digital networks by breaking it down into blocks or packets for more efficient transfer using various network devices. Each time one device sends a file to another, it breaks the file down into packets so that it can determine the most efficient route for sending the data across the network at that time. The network devices can then route the packets to the destination where the receiving device reassembles them for use.

Analyzing Packet Switching technique with respect to following:

A. DELAY:

PROPOGATION DALAY

The types of delays encountered in a packet-switched network are:

• Propagation delay :
  Time taken by the first bit to travel from sender to receiver end of the link.
• Transmission Delay :
  Time taken to put a packet onto link.
• Queuing Delay :
  Queuing delay is the time a job waits in a queue until it can be executed.
• Processing Delay :
  Processing delay is the time it takes routers to process the packet header.

B. RELIABILITY:

The packet switiching process is reliable in that the destination can identify any missing packets . However,circuit switched networks deliver packets in order along the some route and are therefore less likely to experience missing packets in the first place.

C. DATA TRANSMISSION:

In opacket switching ,the data is transfered in small pieces of data across various networks.These down chunks or “packets”allow for Faster ,more efficient data transfer.

D. NETWORK PERFORMANCE:

In network performane , the improved efficiency means less network bandwidth wastage. No need to reserve the circuit even when it’s not in use means the system is good in performance.

E. IMPLEMENTATION:

In packet switching, data packets are first assembled and then numbered. They then travel across a predefined route, sequentially.

F. ERROR HANDLING:

During error like partial outages or other network problem times, packets can be rerouted and follow different paths. Using a circuit switching network, a single outage can down the designated pathway for the communications.

G. APPLICATIONS:

• Packet switching is cost effective ,because switching devices do not need massive amount of secondary storage.
• Packet switching offers improved delay characteristic, because there are no long message in queue.
• Packets can be rerouted if there is any problem, such as busy or disabled links.
• The advantage of packet switching is that ,many network user can share the same channel at the same time.