6 research outputs found
Optimal-Rate Characterisation for Pliable Index Coding using Absent Receivers
We characterise the optimal broadcast rate for a few classes of
pliable-index-coding problems. This is achieved by devising new lower bounds
that utilise the set of absent receivers to construct decoding chains with
skipped messages. This work complements existing works by considering problems
that are not complete-S, i.e., problems considered in this work do not require
that all receivers with a certain side-information cardinality to be either
present or absent from the problem. We show that for a certain class, the set
of receivers is critical in the sense that adding any receiver strictly
increases the broadcast rate.Comment: Authors' cop
Improved Lower Bounds for Pliable Index Coding using Absent Receivers
This paper studies pliable index coding, in which a sender broadcasts
information to multiple receivers through a shared broadcast medium, and the
receivers each have some message a priori and want any message they do not
have. An approach, based on receivers that are absent from the problem, was
previously proposed to find lower bounds on the optimal broadcast rate. In this
paper, we introduce new techniques to obtained better lower bounds, and derive
the optimal broadcast rates for new classes of the problems, including all
problems with up to four absent receivers.Comment: An extended version of the same-titled paper submitted to a
conferenc