Actually cloud services suit wherever standard IT solutions will suit as well. It is a matter of willingness to use a service instead of providing the service by yourself.
When deciding for a cloud service, the first choice is on the delivery model of the service. Assuming you would want to decide upon a CRM solution, there are several ways you may think about cloud support:
- Purchase a CRM-Service from the cloud (SaaS)
- Purchase a Database-Service from the cloud to run your CRM on (PaaS)
- Purchase the Infrastructure you will host the CRM solution on (IaaS)
- Do all on-premise
See the given links for details on the different delivery models.
Your decision will highly depend on the factors Time and Integration need. If you already have many systems available on premise the tendency towards #4 might be stronger as if you don't. One reason for that is the existing capability to organize operational complexity for such a system.
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