By: Shadi Hajibagheri Shadi.hajibagheri66@gmail Mazandaran

By: Shadi Hajibagheri [email protected] Mazandaran University of Science and Technology Supervisor: Hadi Salimi

Definition 2 /20 The SLA is a contract negotiated and agreed between a customer and a service provider

requirements 3 /20 SLA format should clearly describe a service Present the level of performance of service Define ways by which the service parameters can be monitored Penalties when service requirements are not met

SLA Components 4 /20 Purpose Restrictions Validity period Scope Parties Service-level objectives (SLO) Penalties

SLA Lifecycle 5 /20

Discover service provider 6 /20 In cloud computing environments it is important to locate resources that can satisfy consumers requirement efficiently and optimally Resources are owned and operated by various providers

Define-SLA 7 /20 it is necessary to identify the various elements of an SLA that will be signed by agreeing metrics elements : QoS parameters, performanc , measurement,

Stablish Agreement 8 /20 In this step an SLA template is constructed template has to include all aspects of SLA components

Monitor SLA violation 9 /20 It plays a critical role in determining whether SLOs are achieved or violated unfulfillm en

Terminate SLA 10 /20 a key aspect is to decide when it should be terminated once decided, all associated configuration information is removed from the service systems who is the party that triggered this activity what are the consequences of it

Enforce penalties 11 /20 A penalty clause can be applied to the party who violates SLA terms a direct financial compensa-tion being negotiated and agreed between parties SLA violation has two indirect side impacts on providers Consumers use less service from the provider provider’s reputation decreases

SLA Metrics for cloud services 12 /20 SLA SLA SLA SLA metrics metrics metrics metrics for for for for IaaS PaaS SasS Storage as a service

SLA metrics for IaaS 13 /20 Parameter Description CPU capacity CPU speed for VM Memory size Cash memory size for VM Boot time Time for VM to be ready for use Storage storage size of data Scale up Max of VMs for one user Scale down Min number of VMs for one user Scale up time Time to increase number of VMs Scale down time Time to decrease number of VMs Availability Uptime of service in specific time

SLA metrics for PaaS 14 /20 Parameter Description Scalability Degree of use with large number of online users Pay as you go billing Charging based on resources or time of service Servers Browsers Firefox , IE xplorer , .

SLA metrics for SasS 15 /20 Parameter Description Scalability Using with individual or large organisations Availability Uptime of software for users in specific time Customizability Flexible to use with different types of users

16 /20 SLA metrics for Storage as a service Parameter Description Geographic location Availability zones in which data are stored Scalability Ability to increase or decrease storage space Storage billing How the cost of storage is calculated Security Cryptography for storage , authentication , authorization , Privacy How the data will be stored and transferred Backup How and where images of data are stored Recovery Ability to recover data in disasters or failures Transferring bandwidth The capacity of communication channels

SLA negotiation 17 /20 The first scenario involves direct negotiation between the cloud consumer and the cloud service provider The second scenario is negotiation via trusted agent In the third scenario more than one agent is used to carry out the one type of negotiation

SLA-Oriented Architecture 18 /20

19 /20 SLA Management Frameworks and Languages Bilateral Protocol WS-Agreement Web Service Level Agreement (WSLA) WSOL SLAng QML QuO

WSLA WSLA is a framework developed by IBM to specify and monitor SLA for Web Services WSLA consists of a set of concepts and a XML language WSLA comprises of mainly three entities. parties SLA paramete rs 20 /20 SLO

WSLA Architecture 21 /20

Related work 22 /20 SLA@SOI provides two major benefits to the provisioning of services - service predictability - automation

Conclusion 23 /20 service level agreement is the key to ensure a service provider delivers the agreed terms of services cloud consumers with SLA parameters and negotiation can increase trust level of relationship We can manage SLAs with languages like WSLA, WS-Agreement

Refrences 24 /20 [1] M.Alhamad, T.Dillon, E.Chang, (2010), Conceptual SLA Framework for Cloud Computing”, 4th IEEE International Conference on Digital Ecosystems and Technologies (IEEE DEST 2010) 2010 IEEE P.Patel, A.Ranabahu, A.Sheth, “Service Level ]2[ Agreement in Cloud Computing”, Knoesis Center, .Wright State University, USA

Refrences 25 /20 L.Wu, R.Buyya, “Service Level Agreement (SLA) in ]3[ Utility Computing Systems”, The University of Melbourne, .Australia [4] I.Brandic, V.Emeakaroha, M.Maurer, S.Dustdar, (2010) “LAYSI: A Layered Approach for SLA-Violation Propagation in Self-manageable Cloud Infrastructures”, 2010 34th Annual IEEE Computer Software and Applications Conference Workshops. [5] J.Oriol Fit o, I. Goiri, J.Guitart, “SLA-driven Elastic Cloud Hosting Provider”, Technical University of Catalonia Barcelona, Spain.

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