Difference between Encapsulation and Tunneling

Encapsulation vs Tunneling

Encapsulation and tunneling are two important concepts found in computer networks. Tunneling is a method used to transfer a payload (a frame or a packet) from one protocol using an inter-network infrastructure from another protocol. Since the transmitted payload belongs to a different protocol, it cannot be sent because it is created. Encapsulation is the process of encapsulating the payload with an additional header so that it can be sent (tunneled) correctly over the intermediate network. After transmission, the encapsulated payload must be decapsulated at the routing termination point and can be transferred to the final destination. The whole encapsulation process, Transmission and subsequent decapsulation is called tunneling. However, tunneling is sometimes called encapsulation (source of confusion) and.

What is tunneling ??

Tunneling is a method used to transfer the payload of one protocol using an inter-network transport medium of another protocol. The data to be transferred are generally frames / packets belonging to a certain protocol (different from the protocol used to send data). Therefore, the payload cannot be sent because it is produced by its origin.

Therefore, the frames must be wrapped in an additional header, which provides the routing information necessary to transmit the data correctly, before sending. Then, a tunnel (a logical path interconnecting the end points between which the frames must travel) is created and the frames are routed between the end points of the tunnel via the inter-network.

When the encapsulated packets reach the final destination point of the tunnel, they are decapsulated and the original packets contained inside are sent to the desired destination. This overall process, including encapsulation and decapsulation, is called tunneling.

Layers 2 and 3 (of the open systems interconnection reference model) use tunneling. Typical layer 2 tunneling protocols are PPTP (point-to-point tunneling protocol) and L2TP (layer 2 tunneling protocol). Layer 3 typically uses IPSec tunnel mode as the tunneling protocol. encapsulation and de-capsulation, is called tunneling.

What is encapsulation ??

As mentioned above, encapsulation is the process of wrapping packets in an additional header before tunneling. This additional header contains the routing information necessary to send the encapsulated payload through the intermediate inter-network. This information is essential because the useful data is sent via a network (protocol) different from the network in which the data was created. In layer 2 (which uses frames as an exchange unit), the PPTP and L2TP tunnels both encapsulate in a PPP (point-to-point protocol) frame. In layer 3 (which uses packets as an exchange unit), IPSec tunnel mode encapsulates IP (Internet Protocol) packets with an additional IP header.

What is the difference between Encapsulation and Tunneling? 


  • Tunneling is a method used to transfer the payload of one protocol using an internetwork infrastructure of another protocol.
  • Encapsulation is the process of encapsulating the frame with an additional header so that it can be sent (tunneled) correctly via the intermediate network.
  • Tunneling refers to the whole process of encapsulation, transmission and de-capsulation, while encapsulation is only one step in this process.
  • However, regardless of this entire relationship, tunneling is sometimes also called encapsulation.

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