Difference between Connection less and connection oriented Services

Parameter	Connection Less Service	Connection Oriented Service
Definition	It is the Communication System in which there is no need to establish virtual connection between sender and receiver.	It is the communication system in which virtual connection is established between sender and receiver before the communication begins.
Data Acknowledge	No data acknowledge is used, sender can not be sure about the accurate delivery of the message.	Receiver can acknowledge the data send by the sender and can re request the data if any packet fails or gets damaged.
Connection Termination	No Need of Connection termination.	Connection needs to be terminated after completion of communication.
Packet Route	Packets follow different path to reach destination and may reach in any order.	All the frames are sent through same route or path.
Example	Postal System	Telephone Call

Key terms Used:

Sender: The individual that initiates a message in communication system is called sender. Anybody e.g. A speaker, Writer or somebody who merely gestures can be a sender.

Receiver: Reader, Observer or Listener in the communication system is called receiver.

Channel: Physical transmission medium through which message is passed from sender to receiver is called communication channel. That may be wired or wireless.

Protocol: These are the pre-defined, pre-agreed rules between sender and receiver for the communication.

Transmission: It is the process of sending and receiving digital and analog signals over wired and unwired network media.

Packets: It is the formatted data unit used in packet switched networks. Packets contain two types of data:

• Control Information: It Provides information like sender, receiver, communication path, error control and detection bits etc.
• User Data: Actual data to be sent.

Data Acknowledge: It is the signal passed between communicating processes to signify receipt of response, as a part of communication protocol.

Difference between Connection less and connection oriented Services
Difference between Connectionless and Connection Oriented Protocols
Connectionless vs Connection Oriented