So far, the cryptographic techniques we’ve discussed rely on keys that are known by both sender and recipient.

到目前为止，我们讨论的加密技术依赖于发送者和接收者都知道的密钥。

" Crypto" refers to the various encryption algorithms and cryptographic techniques that safeguard these entries, such as elliptical curve encryption, public-private key pairs, and hashing functions.

“加密”指的是各种加密算法和加密技术，保护这些记录的安全性，如椭圆曲线加密、公私钥对和哈希函数。