Pliable index coding studies flexible communication networks where each receiver just needs to receive any message that it does not already have. In this work, we consider a more practical but restricted scenario where each receiver wants any message it does not have from a particular subset of messages. We first adapt coding schemes from pliable index coding to this new restricted pliable index coding setting. We show that the adapted scheme is optimal under certain conditions. We simplify the computational complexity when constructing coding schemes for restricted pliable index coding from exponential to linear. We also construct two new coding schemes for the restricted setting, which can outperform the adapted scheme.

For communications in the presence of eavesdroppers, random components are often used in code design to camouflage information from eavesdroppers. In broadcast channels without eavesdroppers, Marton coding comprises random components which allow correlation between auxiliary random variables representing independent messages. In this paper, we study if Marton coding alone can ensure individual secrecy in the two-receiver discrete memoryless broadcast channel with a passive eavesdropper. Our results show that this is possible and Marton coding guarantees individual secrecy in accordance to the principle of Wyner secrecy coding. However, this comes with a penalty of requiring stricter channel conditions.

This paper studies the problem of secure communication over the two-receiver discrete memoryless broadcast channel with one-sided receiver side information and with a passive eavesdropper. We proposed a coding scheme which is based upon the superposition-Marton framework. Secrecy techniques such as the one-time pad, Carleial-Hellman secrecy coding and Wyner secrecy coding are applied to ensure individual secrecy. This scheme is shown to be capacity achieving for some cases of the degraded broadcast channel. We also notice that one-sided receiver side information provides the advantage of rate region improvement, in particular when it is available at the weaker legitimate receiver.