So many sci-fi authors exploring interstellar civilizations toss in some sort of faster-than-light travel or wormholes to facilitate the narrative. What I liked about Vinge was he considered how things might play out if you actually stuck to the laws of physics as we know them today.
He imagined a nomadic society which moves from star system to star system mostly trading knowledge. While they travel at sub-light speeds, they broadcast a galactic Internet's worth of data at the speed of light. The catch is that much of it is encrypted and only they have the keys, so they have tremendous power wherever they go.
This is not to say he never considered FTL, but when he did, he went deep into its implications. It was not just a means of hopping quickly around the galaxy. He realized that it would enable outrageously powerful AI, as the speed of thought would be increased by orders of magnitude.