a memory called empire

 An newly ambassador from a space-stations confederations is sent to an empire. These stations have the particularity of adding an "image" of a person unto them. She received the previous ambassador but, his last "image", was 15 years old. Coming to the empire, she discovers that her predecessor was killed. Or at least died in mysterious circumstances. She investigates and discovers that the empire is at a problematic succession moment and that her predecessor promised the current emperor the "image" technology, which is a taboo technology for that empire. 
 In the end she and the emperor helpers find a good solution for the succession and she asks to go back to the stations. 

 It was a great book. 
It was about empire-like culture and its perpetuity, compared to the perpetuity of individuals. It's also about station-like psyche compared to planet psyche, and it was really well written