Asymmetric Key Cryptography
Apress eBooks · 2007
This chapter continues our discussion of cryptography by examining asymmetric key cryptography. In the previous chapter, we covered symmetric key cryptography. The problem with symmetric key cryptography is that any two parties that want to exchange confidential information with each other need to agree on a key beforehand. Alice needs to somehow tell Bob the key in order for him to decrypt a message that she sends him. Alice and Bob could meet in person to agree on a key—but this is not usually possible in an Internet transaction. How should they agree upon a key?