Is it possible to use existing on premise AD with Azure/AWS hosted SharePoint 2013?:
You can extend their on premise AD with Active Directory Federation Services (ADFS). Since SharePoint 2013 supports claims based authentication, they can then leverage ADFS as an identity provider for their SharePoint 20103 Virtual Machines.
is it possible to make the load balancing with 2 web front servers: Windows Azure Virtual Machines have built in load balancers that customers can use to load balance their SharePoint Virtual Machines.There are two levels of load balancing available for Azure infrastructure services:
- DNS Level: Load balancing for traffic to different cloud services
located in different data centers, to different Azure websites
located in different data centers, or to external endpoints. This is
done with Traffic Manager and the Round Robin load balancing method.
- Network Level: Load balancing of incoming Internet traffic to
different virtual machines of a cloud service, or load balancing of
traffic between virtual machines in a cloud service or virtual
network. This is done with the Azure load balancer.
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