Cloud computing allows enterprises or users to access resource pools on demand service through the Internet network. In fact, this trend has been materialized as a low-cost way to develop IT infrastructure solutions. However copyrighted cloud service providers seem very costly due to the services required. However, Open-Source cloud systems, provide affordable, reliable, powerful and the cheapest solutions. For this purpose, our investigations will be focusing on Delivering Cloud Services based SLAs on Open-Source Cloud, built and implemented within open sources tools and accessible through internet. On the other hand, using Open-Source Cloud platforms for delivering cloud Services triggers some severe issues Cloud vendors and Cloud consumers. Then, an entity of solution named SLA which is used to solve most issues between those main cloud actors. To accost these issues, we suggest Service Level Agreements (SLAs) that offer best profits for both cloud actors, and we brought out investigations by classifying open sources cloud platforms. The results reveal the effectiveness of SLA for both cloud actors such as cloud vendor and cloud consumer.