{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/120286"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/120286","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Churn-tolerant leader election on weakly-consistent membership","abstract":"Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-09-01 without embargo terms","abstract_html":"Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-09-01 without embargo terms","abstract_has_math":false,"creators":["Wang, Jiangran"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"M.S.","degree_level":"Thesis","degree_discipline":"Electrical & Computer Engr","degree_department":null,"school":null,"contributors":["Gupta, Indranil"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2023,"date_issued":"2023-05","date_published":"2023-05","updated_at":"2026-07-22T22:24:57Z","subjects":["Leader Election","Membership","Churn","Internet Of Things"],"languages":["en","eng"],"rights":["Copyright 2023 Jiangran Wang"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/2142/120286","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Gupta, Indranil"]},{"key":"dc:creator","label":"Author","values":["Wang, Jiangran"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2023-05","2023-04-19"]},{"key":"dc:type","label":"Dc Type","values":["text","Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Electrical & Computer Engr"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M.S."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Leader Election","Membership","Churn","Internet Of Things"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en","eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2023 Jiangran Wang"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://hdl.handle.net/2142/120286"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-09-01 without embargo terms","The student, Jiangran Wang, accepted the attached license on 2023-04-18 at 15:23.","The student, Jiangran Wang, submitted this Thesis for approval on 2023-04-18 at 15:37.","This Thesis was approved for publication on 2023-04-19 at 15:53.","DSpace SAF Submission Ingestion Package generated from Vireo submission #19033 on 2023-09-01 at 17:08:55","Many distributed systems suffer from churn, such as peer-to-peer file-sharing networks and distributed database systems. Churn in distributed systems is the frequent joining and leaving of nodes, leading to instability and challenges in coordination. Distributed applications running in such systems require underneath them a membership protocol that updates (local) membership lists in spite of churn. On top of this membership layer run coordination protocols including (but not limited to) leader election, mutual exclusion, agreement, etc. In this thesis, we present: i) a membership protocol called Medley-F; ii) a family of leader election protocols that are churn-tolerant; and iii) two protocols that estimate churn in distributed systems. First, we present Medley-F, a weakly-consistent membership protocol for IoT networks. It is an enhanced version of an existing system (Medley), and Medley-F utilizes active and passive strategies to reduce failure detection tail latency. We show both simulation results, as well as deployment results, atop Raspberry Pi devices. Second, we present a family of four leader election protocols that are churn- tolerant (or c-tolerant). The key ideas are to: i) involve the minimum num- ber of nodes necessary to achieve safety; ii) use optimism so that decisions are made faster when churn is low; iii) incorporate a preference for elect- ing healthier nodes as leaders. We present experimental results from both a trace-driven simulation and our implementation atop Raspberry Pi devices, including a comparison against Zookeeper. Third, we present two protocols to dynamically estimate churn with the underlying membership changes continuously. The key ideas are to: i) sample memberships from a small subset of nodes; ii) utilize intermediate results during leader election. We show simulation results of the estimation accuracy of both protocols and the effect of underestimating churn on leader election safety."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Churn-tolerant leader election on weakly-consistent membership"]}]}],"canonical_facts":{"dc:contributor":["Gupta, Indranil"],"dc:creator":["Wang, Jiangran"],"dc:date":["2023-05","2023-04-19"],"dc:description":["Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-09-01 without embargo terms","The student, Jiangran Wang, accepted the attached license on 2023-04-18 at 15:23.","The student, Jiangran Wang, submitted this Thesis for approval on 2023-04-18 at 15:37.","This Thesis was approved for publication on 2023-04-19 at 15:53.","DSpace SAF Submission Ingestion Package generated from Vireo submission #19033 on 2023-09-01 at 17:08:55","Many distributed systems suffer from churn, such as peer-to-peer file-sharing networks and distributed database systems. Churn in distributed systems is the frequent joining and leaving of nodes, leading to instability and challenges in coordination. Distributed applications running in such systems require underneath them a membership protocol that updates (local) membership lists in spite of churn. On top of this membership layer run coordination protocols including (but not limited to) leader election, mutual exclusion, agreement, etc. In this thesis, we present: i) a membership protocol called Medley-F; ii) a family of leader election protocols that are churn-tolerant; and iii) two protocols that estimate churn in distributed systems. First, we present Medley-F, a weakly-consistent membership protocol for IoT networks. It is an enhanced version of an existing system (Medley), and Medley-F utilizes active and passive strategies to reduce failure detection tail latency. We show both simulation results, as well as deployment results, atop Raspberry Pi devices. Second, we present a family of four leader election protocols that are churn- tolerant (or c-tolerant). The key ideas are to: i) involve the minimum num- ber of nodes necessary to achieve safety; ii) use optimism so that decisions are made faster when churn is low; iii) incorporate a preference for elect- ing healthier nodes as leaders. We present experimental results from both a trace-driven simulation and our implementation atop Raspberry Pi devices, including a comparison against Zookeeper. Third, we present two protocols to dynamically estimate churn with the underlying membership changes continuously. The key ideas are to: i) sample memberships from a small subset of nodes; ii) utilize intermediate results during leader election. We show simulation results of the estimation accuracy of both protocols and the effect of underestimating churn on leader election safety."],"dc:format":["application/pdf"],"dc:identifier":["https://hdl.handle.net/2142/120286"],"dc:language":["en","eng"],"dc:rights":["Copyright 2023 Jiangran Wang"],"dc:subject":["Leader Election","Membership","Churn","Internet Of Things"],"dc:title":["Churn-tolerant leader election on weakly-consistent membership"],"dc:type":["text","Thesis"],"thesis:degree_discipline":["Electrical & Computer Engr"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["M.S."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:24:57Z"}