Achieving Secrecy Capacity of the Wiretap Channel and Broadcast Channel with a Confidential Component

Understand

The wiretap channel model of Wyner is one of the first communication models with both reliability and security constraints.

• Capacity-achieving schemes for various models of the wiretap channel have received considerable attention in recent literature.
• In this paper, we show that capacity of the general (not necessarily degraded or symmetric) wiretap channel under a "strong secrecy constraint" can be achieved using a transmission scheme based on polar codes.
• We also extend our construction to the case of broadcast channels with confidential messages defined by Csisz{\'a}r and K{\"orner}, achieving the entire capacity region of this communication model.