To invoke multiple async WCF service calls within a WCF service

I have a scenario for WCF service A implementation where in one one WCF service interface method make multiple async calls to 4 separate WCF service interfaces to get some data (all 4 services have separate set of methods interacting to different servers over internet to get some data basis the input provided). The data thus returned to the WCF service A will be collated & maintained in cache & then will be used to make further 4 subsequent async calls to these 4 separate WCF services for different methods from WCF service A.

The wcf service A will be invoked from a portal asynchronously supplying the input parameters.

I would like to know if any one out here has ever done something like this & if yes then any challenges faced?

Or else how to achieve this kind of functionality using some other concept keeping the first level WCF service intact...

Thanks,

A

Source: http://social.msdn.microsoft.com/Forums/en-US/wcf/thread/94f73426-95ab-467d-8ce4-7cded1b8990b

data architecture inca architecture architecture books high availability architecture enterprise application integration architecture