QoS based Cloud Service Selection paradigms

Cloud computing is an emerging trend of 21st century. From last few decades, IT industry and academic researchers are shifting to this paradigm very rapidly. Another side of this issue is they are confused while taking the decision of selecting the provider of cloud services. There are number of Cloud Service Providers (CSPs) in the market, who are providing different cloud services viz Software-as-a-Software, Platform-as-a-Service and Infrastructure-as-a-Service. CSPs are delivering their services to the user based on SLA (Service Level Agreement) document. In this document all the negotiations have been clearly defined, what quality of service will provider give and what the consumer will have to pay have been objectively defined. But unfortunately SLA is not properly followed; quality of service is not up to the mark, breaches in the services are there. In many occasions, availability of service is not there, reliability is compromised, response time is more than what is expected, throughput is not up to the mark and cost factor is fluctuating. In this paper, we will discuss quality of service issues while selecting any cloud services. Researchers and business agents will surely get benefits from the present study.