Editing Service-level agreement (section)

===Cloud computing===
The underlying benefit of [[cloud computing]] is shared resources, which are supported by the underlying nature of a shared infrastructure environment. Thus, SLAs span across the cloud and are offered by service providers as a service-based agreements rather than a customer-based agreements. Measuring, monitoring and reporting on cloud performance is based on the end UX or their ability to consume resources. The downside of cloud computing relative to SLAs is the difficulty in determining the root cause of service interruptions due to the complex nature of the environment.

As applications are moved from dedicated hardware into the [[Cloud computing|cloud]], they need to achieve the same even more demanding levels of service than classical installations. SLAs for cloud services focus on characteristics of the data center and more recently include characteristics of the network (see [[Carrier Cloud|carrier cloud]]) to support end-to-end SLAs.<ref name="RuedaTheServ11">{{cite book |url=https://books.google.com/books?id=z306GUfFL5gC |chapter=The Service Aggregator Use Case Scenario |title=Service Level Agreements for Cloud Computing |author1=Rueda, J.L. |author2=Gómez, S.G. |author3=Chimento, A.E. |editor1=Wieder, P. |editor2=Butler, J.M. |editor3=Theilmann, W. |editor4=Yahyapour, R.  |publisher=Springer Science+Business Media, LLC |pages=329–342 |year=2011 |isbn=9781461416142}}</ref>

Any SLA management strategy considers two well-differentiated phases: negotiating the contract and monitoring its fulfillment in real-time. Thus, SLA management encompasses the SLA contract definition: the basic schema with the [[Quality of service|QoS]] parameters; SLA negotiation; SLA monitoring; SLA violation detection; and SLA enforcement—according to defined policies.{{citation needed|date=April 2022}}

The main point is to build a new layer upon the grid, cloud, or [[Service-oriented architecture|SOA]] middleware able to create a negotiation mechanism between the providers and consumers of services. An example is the EU–funded Framework 7 research project, SLA@SOI,<ref name="ButlerMotiv11">{{cite book |url=https://books.google.com/books?id=z306GUfFL5gC |chapter=Motivation and Overview |title=Service Level Agreements for Cloud Computing |author1=Butler, J.M. |author2=Yahyapour, R. |author3=Theilmann, W. |editor1=Wieder, P. |editor2=Butler, J.M. |editor3=Theilmann, W. |editor4=Yahyapour, R.  |publisher=Springer Science+Business Media, LLC |pages=3–12 |year=2011 |isbn=9781461416142}}</ref> which is researching aspects of multi-level, multi-provider SLAs within service-oriented infrastructure and cloud computing, while another EU-funded project, VISION Cloud,<ref name="VillariHowTo12">{{cite book |url=https://books.google.com/books?id=SB-6BQAAQBAJ |chapter=How to Federate VISION Cloud through SAML/Shibboleth Authentication |title=Service-Oriented and Cloud Computing |author1=Villari, M. |author2=Tusa, F. |author3=Celesti, A. |author4=Puliafito, A. |editor1=De Paoli, F. |editor2=Pimentel, E. |editor3=Zavattaro, G.  |publisher=Springer-Verlag Berlin Heidelberg |year=2012 |pages=259–274 |isbn=9783642334276}}</ref> has provided results concerning content-oriented SLAs.

FP7 IRMOS also investigated aspects of translating application-level SLA terms to resource-based attributes to bridge the gap between client-side expectations and cloud-provider resource-management mechanisms.<ref name="BonifacePlat10">{{cite book |author1=Boniface, M. |author2=Nasser, B. |author3=Papay, J. |title=2010 Fifth International Conference on Internet and Web Applications and Services |chapter=Platform-as-a-Service Architecture for Real-Time Quality of Service Management in Clouds |display-authors=etal |pages=155–160 |year=2010 |doi=10.1109/ICIW.2010.91|isbn=978-1-4244-6728-0 |s2cid=8631786 |chapter-url=https://eprints.soton.ac.uk/271078/1/2010_-_21078.pdf }}</ref><ref name="CuomoAnSLA13">{{cite journal |title=An SLA-based Broker for Cloud Infrastructures |journal=Journal of Grid Computing |author1=Cuomo, A. |author2=Di Modica, G. |author3=Distefano, S. |display-authors=etal |volume=11 |issue=March 2013 |pages=1–25 |year=2013 |doi=10.1007/s10723-012-9241-4|s2cid=10203057 }}</ref> A summary of the results of various research projects in the area of SLAs (ranging from specifications to monitoring, management and enforcement) has been provided by the European Commission.<ref name="KyriazisCloud13">{{cite web |url=https://ec.europa.eu/digital-single-market/news/cloud-computing-service-level-agreements-exploitation-research-results |title=Cloud Computing Service Level Agreements - Exploitation of Research Results |editor=Kyriazis, D. |publisher=European Commission |pages=51 |date=June 2013 |access-date=22 June 2016}}</ref>