Now-a-days, cloud computing is considered as one of the emerging areas in the various fields related to computer science in one way or another. It deals with on demand dynamic resource allocation for providing reliable and guaranteed services to the consumer. It is based on pay-as-you-use model to public. Resource allocation is performed with the objective of minimizing the costs related with it. The tasks of resource allocation are meeting customer demands and application requirements. In this paper, different resource allocation policies have been surveyed based on the different parameters and the related gaps have been discussed.