channel state information i.e., when $\rvs^n$ is revealed to both the transmitter and the legitimate receiver.

Achievability for Theorem \[thm:symCSI\]
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As explained in section \[subsec:CSI\] the achievability result follows directly from Theorem \[thm:lbNoDisc\] by replacing $\rvyr$ with ${\bar{\rvyr}}= (\rvyr,\rvs)$ in the lower bound expression. We nevertheless provide an alternate scheme that only requires the knowledge of causal CSI at the transmitter. The idea is to use a different wiretap codebook for each realization of the state variable. In particular suppose that $\cS = \{s_1,\ldots, s_M\}$ denote the set of available states. Since the encoder and the decoder are both aware of the state realization $\rvs_i$ and can use this common knowledge to select the appropriate codebook for transmission. These codebooks are constructed assuming that the eavesdropper is also revealed the state. Suppose that we fix the distribution $p_{\rvu,\rvx|\rvs=\rvs_i}(\cdot)$ in . Let $$\label{eq:Ri}R_i = I(\rvu;\rvyr|\rvs = s_i)-I(\rvu;\rvye|\rvs=s_i)$$ and $p_i = \Pr(\rvs = s_i)$. For each $i=1,2\ldots, M$, a wiretap codebook of length $np_i$ and rate $R_i$ is constructed and used to transmit a message ${\mathsf{\kappa}}_i$. Another independent key ${\mathsf{\kappa}}_s$ of rate $R_s = H(\rvs|\rvye)$ is then generated by exploiting the fact that $\rvs^ n$ is not known to the eavesdropper.

