Secret-key generation Sample Clauses
Secret-key generation. We now appropriately bound each term in (33). First note that since the sequence un is uniformly distributed among the set of all possible codeword sequences, it follows that n • The decoder upon observing yr finds a sequence un r jointly typical with y n.
1 H(un) = log2 |C| • Both encoder and the decoder declare the bin-index of un to be the secret-key.
Secret-key generation e wkck e ′ We can now estimate I(Qk; Re ) in (11) by replacing the = gk − ek,2 + 1 + w2c ek,1 = gk − ek,2 + ek,1, (22) ▇ ▇ ▇ where (a) is due to the fact that the conditional mean value true value of gk with its estimate, gˆk derived in the previous subsection. Let us denote the estimate of I(Qk; Re ) based on e whch √ζh gˆe by I(Qk; Rˆe ) with which the length of secret key is now of gk for given gk and ζk is 1+w2 c ( c M − gk) as shown k k in Appendix D, and e adaptively determined as +
Secret-key generation. Pr(ΓA ƒ= Γ [ ΓB Γ) ≤ δ(ε). (164) Our analysis thus far has established the existence of a codebook C˜⊗ that generates a common tuple of sequences .ΣuKΣ, Σy¯K Σ , Σy¯K Σ Σ , satisfies the equivocation constraint (136) and the reliability constraint (164). We next discuss how one can use the codebook C˜⊗ to generate a common secret-key at the two terminals. We consider transmission over a total of M macro-blocks. Each macro-block i spans K coherence blocks the terminals sample sequences ¯xK(i) and ¯xK(i) in an i.i.d. fashion, independently from the previous blocks. Thereafter we execute the steps discussed in the previous sections, which results in the following observations at the legitimate receivers and the eavesdropper: ΓA(i) = .ΣuˆK(i)Σ , ΣyK
(i) Σ , ΣyˆK
(i) Σ Σ (165)
Secret-key generation. The control unit runs SKeyGen algorithm to generate secret keys for communicating bio-sensors. It takes cer- tificate Certr, certificate Certs, public key g1 and master key g2 as inputs, and outputs secret key pairs SKs and SKr. For the sender, the control unit selects a random number s ∈ Zp, computes SKs and sends it to the sender. SKs = {SKs1, SKs2} = {g2 · hs·Certs , gs} (9) For the receiver, it selects a random number r Zp, computes SKr and sends it to the receiver. r·Certr rSKr = {SKr1, SKr2} = {g2 · h , g } (10) It is important to note that secret key pairs SKs can only be known by the sender and the control unit, and SKr can only be known by the receiver and the control unit.