* Security
* Security is the main concern in IaaS as it is not 100percent sure.
* Maintenance and up gradation
* Although IaaS providers maintain the software but not for all.
* Interoperability issues
* It is difficult to migrate Virtual Machine form one IaaS provider to another, so customers experience problem related to vendor lock.
* Main Iaas Cloud Service providers are Amazon Web Services, Microsoft Azure, and Google Cloud Platform etc.
