TY - JOUR

T1 - Adaptive Relaying for Streaming Erasure Codes in a Three Node Relay Network

AU - Facenda, Gustavo Kasper

AU - Krishnan, M. Nikhil

AU - Domanovitz, Elad

AU - Fong, Silas L.

AU - Khisti, Ashish

AU - Tan, Wai Tian

AU - Apostolopoulos, John

N1 - Publisher Copyright:
© 1963-2012 IEEE.

PY - 2023/7/1

Y1 - 2023/7/1

N2 - This paper investigates adaptive streaming codes over a three-node relayed network. In this setting, a source node transmits a sequence of message packets to a destination with help of a relay. The source-to-relay and relay-to-destination links are unreliable and introduce at most N_1 and N_2 packet erasures, respectively. The destination node must recover each message packet within a strict delay constraint T. The paper presents a new construction of streaming codes for all feasible parameters \N_1, N_2, T\. Our work improves upon the construction in Fong et al. by adapting the relaying strategy based on the erasure patterns from source to relay. Specifically, the code employs the notion of symbol estimates, which allows the relay to forward information about symbols before it can decode that symbol, and variable-rate encoding, which decreases the rate used to encode a packet as more erasures affect that packet. The codes proposed in this paper achieve rates higher than the ones proposed by Fong et al. whenever N_2 > N_1 , and achieve the same rate when N_2 \leq N_1 , in which case the rate is optimal. The paper also presents an upper bound on the achievable rate that takes into account erasures in both links in order to bound the rate in the second link. The upper bound is shown to be tighter than a trivial bound that considers only the erasures in the second link.

AB - This paper investigates adaptive streaming codes over a three-node relayed network. In this setting, a source node transmits a sequence of message packets to a destination with help of a relay. The source-to-relay and relay-to-destination links are unreliable and introduce at most N_1 and N_2 packet erasures, respectively. The destination node must recover each message packet within a strict delay constraint T. The paper presents a new construction of streaming codes for all feasible parameters \N_1, N_2, T\. Our work improves upon the construction in Fong et al. by adapting the relaying strategy based on the erasure patterns from source to relay. Specifically, the code employs the notion of symbol estimates, which allows the relay to forward information about symbols before it can decode that symbol, and variable-rate encoding, which decreases the rate used to encode a packet as more erasures affect that packet. The codes proposed in this paper achieve rates higher than the ones proposed by Fong et al. whenever N_2 > N_1 , and achieve the same rate when N_2 \leq N_1 , in which case the rate is optimal. The paper also presents an upper bound on the achievable rate that takes into account erasures in both links in order to bound the rate in the second link. The upper bound is shown to be tighter than a trivial bound that considers only the erasures in the second link.

KW - Cloud computing

KW - adaptive relay

KW - forward error correction

KW - low-latency

KW - packet erasure channel

KW - relayed network

KW - streaming

KW - symbol-wise decode-and-forward

UR - http://www.scopus.com/inward/record.url?scp=85149841901&partnerID=8YFLogxK

U2 - 10.1109/TIT.2023.3254464

DO - 10.1109/TIT.2023.3254464

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AN - SCOPUS:85149841901

SN - 0018-9448

VL - 69

SP - 4345

EP - 4360

JO - IEEE Transactions on Information Theory

JF - IEEE Transactions on Information Theory

IS - 7

ER -