Online caching and coding at the WiFi edge: gains and tradeoffs

Lalhruaizela Chhangte, Emanuele Viterbo, D. Manjunath, Nikhil Karamchandani

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearchpeer-review

5 Citations (Scopus)


Video content delivery at the wireless edge continues to be challenged by insufficient bandwidth and highly dynamic user behavior which affects both effective throughput and latency. Caching at the network edge and coded transmissions have been found to improve user performance of video content delivery. The cache at the wireless edge stations (BSs, APs) and at the users' end devices can be populated by pre-caching content or by using online caching policies. In this paper, we propose a system where content is cached at the user of a WiFi network via online caching policies, and coded delivery is employed by the WiFi AP to deliver the requested content to the user population. The content of the cache at the user serves as side information for index coding. We also propose the LFU-Index cache replacement policy at the user that demonstrably improves cache hit and index coding opportunities at the WiFi AP for the proposed system. Through an extensive simulation study, we determine the gains achieved by caching and index coding. Next, we analyze the tradeoffs between them in terms of data transmitted, latency, and throughput for different content request behaviors from the users. We also show that the proposed cache replacement policy performs better than traditional cache replacement policies like LRU and LFU.

Original languageEnglish
Title of host publication2020 IEEE Wireless Communications and Networking Conference Workshops, WCNCW 2020
Subtitle of host publicationProceedings
EditorsSong Chong, Sunghyun Choi, Zhisheng Niu
Place of PublicationPiscataway NJ USA
PublisherIEEE, Institute of Electrical and Electronics Engineers
Number of pages6
ISBN (Electronic)9781728151786
ISBN (Print)9781728151793
Publication statusPublished - 2020
EventIEEE Wireless Communications and Networking Conference Workshops 2020 - Seoul, Korea, South
Duration: 25 May 202028 May 2020


ConferenceIEEE Wireless Communications and Networking Conference Workshops 2020
Abbreviated titleWCNCW 2020
Country/TerritoryKorea, South


  • cache
  • edge
  • index coding
  • wireless

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