Elementary Information Security, 3rd Edition

▶ 13.3 Crypto Atop the Protocol Stack

We achieve very important benefits if we apply cryptography at the very top of the application layer or even above the network protocol stack. It is much easier to develop software as an application instead of making changes to OS or networking software (FIGURE 13.15). This also provides the benefits of end-to-end crypto.

Inside the sending host, the ciphertext is generated by encryption of Plain text by application or encryption protocol stack (transport, IP, Link, and Driver). The Cipher text is directed to Driver layer of Router or gateway with IP, Link, and Driver layers. The cipher text from router ...