An encryption system operating on a series of keys, each of which is used only one time; they are considered unbreakable. The encryption can be performed with 128-bit ssl encryption for online security.

The only known form of encryption that is unbreakable. It relies on a random key that is the same length as the message. Each key can be used once and only once.

Manual, one-time, cryptosystem produced in pad form. If the individual sheets in the pad are never reused, this cryptosystem cannot be broken

a block of random data used to encrypt a block of equal length plain text data

a sequence of random bits

a simple encryption method that is provably secure

a unique encryption key that is used only once

Sheets of paper or silk printed with random five-number group ciphers to be used to encode and decode enciphered messages.

A particular cryptographic system that is provably secure in some sense, but highly impractical, because it requires a bit of entropy for every bit of message.

A stack of papers bound together, with each paper providing one large, non-repeating set of truly random letters and/or numbers used as an encryption key. Widely used in World War II, the method consisted of using the key on a page exactly once, then tearing off the page and using the key on the next page for the next message. Since the key changes with every message, the enemy does not have a feasible chance to decrypt any given message; thus, one-time pads are considered the only perfect encryption scheme â€” as long as the bad guys don't intercept a copy of the pad.

A secret-key cipher in which the key is a truly random sequence of bits that is as long as the message itself, and encryption is performed by XORing the message with the key. This is theoretically unbreakable.

In cryptography, the one-time pad (OTP) is an encryption algorithm where the plaintext is combined with a random key or "pad" that is as long as the plaintext and used only once. A modular addition (for example XOR) is used to combine the plaintext with the pad. It was invented in 1917.