Click the Delivery tab, and then click Outbound Connections.
In the Outbound Connections dialog box, click to select the Limit connections to check box, and then type a value for the maximum outbound connections.
By default, the time-out time is set to 600 minutes. Type a new value if you want to change the default value.
Click to select the Limit connections per domain to check box, and then type a value for the number of connections that you want to allow for each domain.
Click OK and then click OK again to close the virtual server properties.