{"id":{"repo_id":"buffalo","oai_identifier":"oai:ubir.buffalo.edu:10477/78553"},"canonical_url":"https://search.dev.ndltd.org/etd/buffalo/oai:ubir.buffalo.edu:10477/78553","repository":{"repo_id":"buffalo","name":"Buffalo","base_url":"https://ubir.buffalo.edu/oai/request"},"display":{"title":"Three Essays on SLA Management in the Availability-aware Cloud","abstract":"Ph.D.","abstract_html":"Ph.D.","abstract_has_math":false,"creators":["Yuan, Shuai"],"institution":"State University of New York at Buffalo","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Das, Sanjukta","Management Science and Systems"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2018,"date_issued":"2018-10-26T02:55:22Z","date_published":"2018-10-26T02:55:22Z","updated_at":"2026-07-27T19:05:12Z","subjects":["management","information technology"],"languages":["eng"],"rights":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10477/78553","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Das, Sanjukta","Management Science and Systems"]},{"key":"dc:creator","label":"Author","values":["Yuan, Shuai"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2018-10-26T02:55:22Z","2018","2018-08-05 17:43:39"]},{"key":"dc:publisher","label":"Institution","values":["State University of New York at Buffalo"]},{"key":"dc:type","label":"Dc Type","values":["Text","Dissertation"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["management","information technology"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/10477/78553"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Ph.D.","A cloud service provider and a client are typically bound by a Service Level Agreement (SLA) articulating various contract constructs, such as service window, price, penalty, and service availability. Service availability is usually specified as an uptime guarantee and major providers presently set a high standard in this regard. The objective of this research is to design and provide a framework for availability-aware SLA management. SLA for cloud services entail complex trade-offs between interrelated variables such as price, penalty, and service availability (uptime) guarantee, with resource management strategies affecting fulfillment of the SLA. In Essay 1, we address three key components of the SLA-based cloud resource management and pricing problem, from the service-provider’s perspective: (1) availability-aware backup resource provisioning; (2) price-penalty schedule determination; and (3) penalty-deferred pricing over two periods. Using the convexity of the provider’s expected total cost over the number of backup resources, we present a dichotomous search algorithm to derive the total cost minimizing number of backup resources for a given level of SLA-specified service availability guarantee. Next, we derive closed-form solutions for the lower bound of the feasible price range, yielding a schedule of breakeven price – penalty combinations, which establishes the baseline required in the economic modeling of the service contracts and related negotiation processes, and may also elicit client preference information. We then model a two-period pricing problem designed specifically to incentivize penalty deferrals in the event of an SLA violation. Detailed experimental studies of the proposed models have been carried out using real-world datacenter log data. The computational study validates the convexity of the probability density function of SLA violations over the number of backup resources. The results demonstrate significant interaction effects between the SLA parameters (price, penalty rate and provisioning cost) and the backup resource provisioning decisions made by the provider, leading to key practical managerial implications for SLA design and resource deployment in the availability-aware cloud.At the commencement of service, the provider can derive the optimal number of backup VMs to mitigate the SLA violation risk, based on the agreed upon SLA constructs, e.g., price, penalty and uptime guarantee following Essay 1. However, initial backups may need to be adjusted in response to real-time failure and repair events. In Essay 2, we first propose a periodic intervention strategy that allows the provider to adjust the allocation of backup resources such that the expected total cost is minimized. We also focus on the limit number of interventions, starting from single intervention strategy, as frequent reallocations may be costly. We present computational results exploring the impact of intervention on the likelihood of SLA violation and downtime distribution for the rest of the contract, and also evaluate certain parameters, such as time and quantum of adjustment, and penalty levels desired by clients, their influences on the backup resource provisioning strategies. Finally, we summarize this study by providing key practical managerial implications for resource deployment in the cloud. Network Function Virtualization (NFV) is a further step in virtualization technologies where traditional hardware-based network appliances are replaced by software-based virtual network functions. An essential challenge in developing resource provisioning strategies from the perspective of a provider is the estimation of availability of service over a service window in the NFV context. While steady-state probabilities can be derived for birth-death processes with regard to failure and repair events, they cannot be established under any service window in practice. In Essay 3, we develop an efficient availability estimation algorithm to derive the availability distribution given the demand of the client. We then propose a backup resource allocation mechanism based on the prediction of availability to meet the uptime guarantee in SLA. This work provides a foundational framework for future research in the area of NFV resource reallocation and availability-aware decision-making framework design, which is likely to gain more traction with the increased commercialization of virtualized network functions."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Three Essays on SLA Management in the Availability-aware Cloud"]}]}],"canonical_facts":{"dc:contributor":["Das, Sanjukta","Management Science and Systems"],"dc:creator":["Yuan, Shuai"],"dc:date":["2018-10-26T02:55:22Z","2018","2018-08-05 17:43:39"],"dc:description":["Ph.D.","A cloud service provider and a client are typically bound by a Service Level Agreement (SLA) articulating various contract constructs, such as service window, price, penalty, and service availability. Service availability is usually specified as an uptime guarantee and major providers presently set a high standard in this regard. The objective of this research is to design and provide a framework for availability-aware SLA management. SLA for cloud services entail complex trade-offs between interrelated variables such as price, penalty, and service availability (uptime) guarantee, with resource management strategies affecting fulfillment of the SLA. In Essay 1, we address three key components of the SLA-based cloud resource management and pricing problem, from the service-provider’s perspective: (1) availability-aware backup resource provisioning; (2) price-penalty schedule determination; and (3) penalty-deferred pricing over two periods. Using the convexity of the provider’s expected total cost over the number of backup resources, we present a dichotomous search algorithm to derive the total cost minimizing number of backup resources for a given level of SLA-specified service availability guarantee. Next, we derive closed-form solutions for the lower bound of the feasible price range, yielding a schedule of breakeven price – penalty combinations, which establishes the baseline required in the economic modeling of the service contracts and related negotiation processes, and may also elicit client preference information. We then model a two-period pricing problem designed specifically to incentivize penalty deferrals in the event of an SLA violation. Detailed experimental studies of the proposed models have been carried out using real-world datacenter log data. The computational study validates the convexity of the probability density function of SLA violations over the number of backup resources. The results demonstrate significant interaction effects between the SLA parameters (price, penalty rate and provisioning cost) and the backup resource provisioning decisions made by the provider, leading to key practical managerial implications for SLA design and resource deployment in the availability-aware cloud.At the commencement of service, the provider can derive the optimal number of backup VMs to mitigate the SLA violation risk, based on the agreed upon SLA constructs, e.g., price, penalty and uptime guarantee following Essay 1. However, initial backups may need to be adjusted in response to real-time failure and repair events. In Essay 2, we first propose a periodic intervention strategy that allows the provider to adjust the allocation of backup resources such that the expected total cost is minimized. We also focus on the limit number of interventions, starting from single intervention strategy, as frequent reallocations may be costly. We present computational results exploring the impact of intervention on the likelihood of SLA violation and downtime distribution for the rest of the contract, and also evaluate certain parameters, such as time and quantum of adjustment, and penalty levels desired by clients, their influences on the backup resource provisioning strategies. Finally, we summarize this study by providing key practical managerial implications for resource deployment in the cloud. Network Function Virtualization (NFV) is a further step in virtualization technologies where traditional hardware-based network appliances are replaced by software-based virtual network functions. An essential challenge in developing resource provisioning strategies from the perspective of a provider is the estimation of availability of service over a service window in the NFV context. While steady-state probabilities can be derived for birth-death processes with regard to failure and repair events, they cannot be established under any service window in practice. In Essay 3, we develop an efficient availability estimation algorithm to derive the availability distribution given the demand of the client. We then propose a backup resource allocation mechanism based on the prediction of availability to meet the uptime guarantee in SLA. This work provides a foundational framework for future research in the area of NFV resource reallocation and availability-aware decision-making framework design, which is likely to gain more traction with the increased commercialization of virtualized network functions."],"dc:format":["application/pdf"],"dc:identifier":["http://hdl.handle.net/10477/78553"],"dc:language":["eng"],"dc:publisher":["State University of New York at Buffalo"],"dc:rights":["Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.","Copyright retained by author."],"dc:subject":["management","information technology"],"dc:title":["Three Essays on SLA Management in the Availability-aware Cloud"],"dc:type":["Text","Dissertation"]},"updated_at":"2026-07-27T19:05:12Z"}