Request/response messaging pattern

All ,

I have a doubt on the Request response pattern... Assume the following is my scenarion

1. I have a service running on Windows Azure. This  service can be called by users to execute a command.
2. I have a client applications that is running on my intranet. This client application will execute the command . The computer in which the client application is running is connected to internet , but does not have a static IP i.e machine cannot be accessed directly via the internet
3. I am planning to use Azure Service Bus through which my service on Windows Azure can communicate with the client application to execute.... 

In this scenario, can i use Request/response messaging i.e can the service post a message and expect a response from the client  

OR

Should i use command queue for each client , the Service will push the command to be executed on a queue , the client will poll the queue and execute a command

Any help is appreciated