Answer with explaination
IaaS(Infrastructure as a service) layer is responsible for user authentication in cloud computing.
Cloud computing is a very powerful/advanced technology which is the on-demand availiblity of computers resources such as devices,servers,virtual machines,data storage backup servers(cloud),computing power etc without the direct active management by users.It comes with pay-as-you-go pricing for using on-demand delivery IT resources.
Iaas is one of the layers of cloud computing along with Saas(Software as a service)&Paas(Platform as a service).It is basically user oriented system which provide authentication based services such as managing,accessing the computer resouces and also monitoring the computer resouces.It avoids the actual buying and complexity of physical servers.Handling such heavy physical servers needs lot of space and this process is very cumbersome.So through cloud computing it becomes easy to handle the servers and other related stuffs.
Azure and Amazon web services are the most popular of providing these services.Iaas is also named as Hardware as a service.It provides network as a service (for switching,networking,routingor bridges for the virtual machines).Apart from it ,it provides load balancer which manage the traffic of data packets precisely.Moreover,it is much more scalable and flexible.
Users can avoide the infrasture setup headache and focus on the core buisness for more growth and opportunities.