Capacity Results for Erasure Broadcast Channels with Intermittent Feedback Recently, we showed that, rather surprisingly, the capacity region of the twouser erasure broadcast channel with global delayed channel state information (CSI) can be achieved with singleuser delayed CSI only. More precisely, we assumed one receiver does not provide its channel state to the other two nodes (the other receiver and the transmitter), while the other receiver reveals its state globally with unit delay. In this work, we consider a more general setting in which feedback links are intermittent. To be precise, at any time instant, each receiver broadcasts its CSI, and this information either becomes available to the other two nodes or gets erased. For this setting, we develop a new set of outer bounds to capture the intermittent nature of the feedback links. These outer bounds depend on the probability that both feedback links are erased rather than the individual erasure probability of each feedback link. This result matches our earlier findings for the singleuser delayed CSI scenario. We also provide a capacityachieving recursive communication protocol for the scenario in which feedback links are fully correlated.

On The Stability Region of the Layered Packet Erasure Broadcast Channel with Output Feedback This paper studies the Layered Packet Erasure Broadcast Channel (LPEBC) with Channel Output Feedback (COF), which is a highSNR approximation of the fading Gaussian BC, proposed by Tse and Yates in 2012 for the case without COF. This model is also a multilayer generalization of the Binary Erasure Channel (BEC). In a past work, the Authors derived inner and outer bounds to the rate region (set of achievable rates with backlogged arrivals) of the LPEBC with COF; here, the arrival region (set of exogenous arrival rates for which packet arrival queues are stable) for the same model is analyzed. For the case of K2 users and Qgeq 1 layers, the known achievable rate region and the derived arrival region coincide; both strategically employ a networkcoding based retransmission protocol. For the case of Q  2 layers, sufficient conditions are given for the achievable arrival region to coincide with the known converse rate region, thus showing that in those cases the optimal rate and arrival regions coincide.