On the Capacity Region of Deterministic Strong IC with Multicast and Secure Unicast Messages

We study a two-user symmetric interference channel (IC) with common and unicast message under security constraints. In this model, one transmitter wants to send a multicast message to both receivers, while the other transmitter intends to send a unicast message to one receiver. The unicast message needs to be protected from the unintended receiver. We establish the capacity region of multicast and secure unicast messages for the case of strong interference, i.e., when the cross links are stronger than the direct links. The achievability scheme demands cooperative jamming in an extended form, where some jamming bits are themselves protected initially and then applied in a subsequent channel use.