  In this paper, capacity bounds for the two-user Interference Channel (IC)
with cooperative receivers via conferencing links of finite capacities is
investigated. The capacity results known for this communication scenario are
limited to a very few special cases of the one-sided IC. One of the major
challenges in analyzing such cooperative networks is how to establish efficient
capacity outer bounds for them. In this paper, by applying new techniques,
novel capacity outer bounds are presented for the ICs with conferencing users.
Using the outer bounds, several new capacity results are proved for interesting
channels with unidirectional cooperation in strong and mixed interference
regimes. A fact is that the conferencing link (between receivers) may be
utilized to provide one receiver with information about its corresponding
signal or its non-corresponding signal (interference signal). As a remarkable
consequence, it is demonstrated that both strategies can be helpful to achieve
the capacity of the channel. Finally, for the case of Gaussian IC, it is
mathematically shown that our outer bound is strictly tighter than the previous
one derived by Wang and Tse.
