Which ports Exchange 2010 uses?, you probably already read the Exchange 2010 Network Port Reference TechNet article located here.
At some point, when discussing with the network/firewall people or documenting your design, it might be required to visualize things. For this purpose you can use the following diagram.
Note that it’s a v1 and not all things are included.
Also, all ports are left at their default values and the diagram doesn’t reflect the fact that you can fix certain ports like the one for the DAG or the MAPI RPC port; that might be added in a later version