
If you are already running Exchange Server On Premises you can use PowerShell or tools like Exchange Server Profile analyzer, in order to determine mailbox size, average message size, messages sent and received per mailbox per day etc. This tool can help you to reduce the risks involved in Exchange Server network bandwidth planning and is suitable for Exchange Online as well as Exchange On Premises. To do this, we are going to use a very useful tool called Exchange Client Network Bandwidth Calculator and you can find it here. In this section we are going to estimate the network bandwidth that your company would need to access Microsoft Exchange Online. For detailed documentation, business requirements, assessment and deployment preparation you can go to OnRamp for Office 365 Microsoft Exchange Online Detailed specifications are beyond the scope of this article.

In this article we are going to provide guidelines for rough (simple) estimation of the network bandwidth, each service is going to consume. The number and the capacity of the network connections and network segments associated with each client computer.The company’s network topology and the capacity of the various pieces of network hardware.The task each client computer is performing.The number of client computers that is in use simultaneously.The online services that your company has subscribed to.When estimating network traffic, there are many variables to consider. Each of these, online provided, services has its own bandwidth requirements.

Microsoft Office 365 combines Microsoft Office desktop suite with cloud-based versions of communication and collaboration services like Microsoft Exchange Online, Microsoft SharePoint Online, Microsoft Office Web Apps, and Microsoft Lync Online.
