Joint Scheduling and Coding Over Lossy Paths With Delayed Feedback
We consider the transmission of packets across a lossy end-to-end network path so as to achieve low in-order delivery delay. This can be formulated as a decision problem, namely deciding whether the next packet to send should be an information packet or a coded packet. Importantly, this decision is made based on delayed feedback from the receiver. While an exact solution to this decision problem is combinatorial in the feedback delay, we exploit ideas from queueing theory to derive scheduling policies that, while suboptimal, can be efficiently implemented and offer substantially better performance than state of the art approaches to making use of delayed feedback. We obtain a number of useful analytic bounds that help characterise design trade-offs and our analysis highlights that the use of prediction plays a key role in achieving good performance in the presence of significant feedback delay. Our approach readily generalises to networks of paths and we illustrate this by application to multipath transport scheduler design.
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