What is SSL Tunneling?
SSL Tunneling involves a client that requires an SSL connection to a backend service or secures a server via a proxy server. This proxy server opens the connection between the client and the backend service and copies the data to both sides without any direct interference in the SSL connection.
Tunneling
A technique of inter-networking called Tunneling is used when source and destination networks of the same type are to be connected through a network of different types. Tunneling uses a layered protocol model such as those of the OSI or TCP/IP protocol suite.
So, in other words, when data moves from host A to B it covers all the different levels of the specified protocol (OSI, TCP/IP, etc.) while moving between different levels, data conversion (Encapsulation) to suit different interfaces of the particular layer is called tunneling.
For example, let us consider an Ethernet to be connected to another Ethernet through a WAN as:
The task is sent on an IP packet from host A of Ethernet-1 to host B of Ethernet-2 via a WAN.