Which practice involves encapsulating a network protocol within another protocol to traverse networks?

Which practice involves encapsulating a network protocol within another protocol to traverse networks?

• A. Encapsulation
• B. Tunneling
• C. VPN
• D. Protocol relay

Answer: (B)

Tunneling is the practice of wrapping one protocol’s data inside another protocol so it can be transported across networks that don’t support the inner protocol. This lets the inner traffic traverse intermediate networks by using the outer protocol for the actual delivery and then decapsulation at the destination. A common real-world example is sending an IP packet inside a GRE or IPsec tunnel; the outer header is routable across the network, while the inner packet is restored at the end. This differs from generic encapsulation, which is just wrapping data in a protocol header without implying traversal across network boundaries. A VPN uses tunneling to create a secure path, but the act being described is tunneling itself. Protocol relay isn’t the standard term for this mechanism.

Tunneling is the practice of wrapping one protocol’s data inside another protocol so it can be transported across networks that don’t support the inner protocol. This lets the inner traffic traverse intermediate networks by using the outer protocol for the actual delivery and then decapsulation at the destination. A common real-world example is sending an IP packet inside a GRE or IPsec tunnel; the outer header is routable across the network, while the inner packet is restored at the end.

This differs from generic encapsulation, which is just wrapping data in a protocol header without implying traversal across network boundaries. A VPN uses tunneling to create a secure path, but the act being described is tunneling itself. Protocol relay isn’t the standard term for this mechanism.