Common use of Review of the Literature Clause in Contracts

Review of the Literature. In this section some of the results on secret-key agreement by perfectly authen- ticated public discussion are reviewed. Xxxxxxx'x [21] famous result on perfect secrecy, stating that a cipher can achieve perfect secrecy only if the entropy of the secret key is at least as large as the entropy of the plaintext, can be considered as a special case (for 1-round protocols) of Theorem 1 below. Although Xxxxx'x wire-tap channel scenario [25] and Xxxxxxx and Kxxxxx'x generalization [8] thereof do not include a public channel between Xxxxx and Xxx, they should neverthe- less be mentioned here. In those scenarios, Xxxxx can send information over a so-called broadcast channel where Bob and Xxx can receive di erent outputs of the channel. Secret information transmission (and hence secret-key agreement) was shown to be possible if and only if Xxx's channel is noisier than Bob's chan- nel [8], an assumption that is generally unrealistic. In the scenario considered in quantum cryptography (see [2] and references therein), Xxxxx can send polarized light pulses of very low intensity to Bob over 3 H(S) = P s: PS (s)>0 PS (s) log 2 PS (s). See [6] for an introduction to the basic con- cepts of information theory.

Review of the Literature. In this section some of the results on secret-key agreement by perfectly authen- ticated public discussion are reviewed. Xxxxxxx'x [21] famous result on perfect secrecy, stating that a cipher can achieve perfect secrecy only if the entropy of the secret key is at least as large as the entropy of the plaintext, can be considered as a special case (for 1-round protocols) of Theorem 1 below. Although Xxxxx'x wire-tap channel scenario [25] and Xxxxxxx and Kxxxxx'x generalization [8] thereof do not include a public channel between Xxxxx and Xxx, they should neverthe- less be mentioned here. In those scenarios, Xxxxx can send information over a so-called broadcast channel where Bob and Xxx can receive di erent outputs of the channel. Secret information transmission (and hence secret-key agreement) was shown to be possible if and only if Xxx's channel is noisier than Bob's chan- nel [8], an assumption that is generally unrealistic. In the scenario considered in quantum cryptography (see [2] and references therein), Xxxxx can send polarized light pulses of very low intensity to Bob over 3 H(S) = P s: PS (s)>0 PS (s) log 2 log2 PS (s). See [6] for an introduction to the basic con- cepts of information theory.