I have read one book in a series about aliens who have been many centuries on earth with a hostile agenda. The book starts with a crew of human explorers who are travelling to a planet in a distant star system. They are in communication with the earth, but communication at some point was sabotaged due to some data glitch with computers on a space center on earth. One of protagonist works with computers monitoring the communication with the explorers.
Parallel story is of an assassin who belongs to some ancient, secret order that is founded by some other group of aliens more friendly to humans. The aliens with the hostile agenda have also founded an order. They have catalyzed the human scientific progress so that humans have to move to the home planet of the aliens. Why? So that they can serve as a food for the alien race.
I would appreciate if you know the title of the book. Thanks!