using multiple io_service objects

I have my application in which listen and process messages from both internet sockets and unix domain sockets. Now I need to add SSL to the internet sockets, I was using a single io_service object for all the sockets in the application. It seems now I need to add separate io_service objects for network sockets and unix domain sockets. I don't have any threads in my application and I use async_send and async_recieve and async_accept to process data and connections. Please point me to any examples using multiple io_service objects with async handlers.