An after-sales service contract is concluded between the supplier and an external customer. There is an internal ALS between the supplier and its internal customer – it can be an organization, a department or another site. Finally, there is a lender ALS between the provider and the lender. The ALS should contain not only a description of the services to be provided and their expected levels of service, but also metrics to measure the services, obligations and responsibilities of each party, corrective measures or penalties in the event of a breach, and a protocol for adding and removing measures. These systems and processes are often controlled by specialized third-party companies. If this is the case, it is necessary that the third party is also involved in the AES negotiations. This will allow them to obtain details of the levels of service that should be monitored and explanations on how to prosecute them. Stakeholders — Clearly defines and defines the responsibilities of the parties to the agreement. One of the key elements of a service level agreement is that the objective should be to fairly integrate good practices and requirements that maintain service and avoid additional costs. Service level agreements are also defined at different levels: a service level contract (SLA) is the service contract component between a service provider and a customer. ALS offers specific and measurable aspects related to the services offered.
For example, ALS is often included in agreements signed between internet service providers (Internet service providers, ISPs) and customers. Cloud computing is a fundamental advantage: shared resources, supported by the underlying nature of a common infrastructure environment. SLAs therefore extend to the cloud and are offered by service providers as a service-based contract and not as a customer-based agreement. Measuring, monitoring and covering cloud performance is based on the final UX or its ability to consume resources. The disadvantage of cloud computing compared to ALS is the difficulty of determining the cause of service outages due to the complex nature of the environment. SLAs often include many elements, from the definition of services to the termination of the contract.  In order to ensure rigorous compliance with ALS, these agreements are often designed with specific lines of demarcation and the parties concerned must meet regularly to create an open communication forum. Rewards and penalties that apply to the supplier are often set. Most ALS also leave room for regular (annual) revisions to make changes.  The main point is the construction of a new level for the soA network, cloud or middleware, capable of creating a trading mechanism between service providers and consumers.
For example, the EU-funded Framework SLA@SOI 7 research projectexplores aspects of multi-level, multi-supplier slas within service-based infrastructure and cloud computing, while another EU-funded project, VISION Cloud, has delivered results in terms of content-based ALS.