This novel, and the prequel A Deepness in the Sky, depict a human interstellar civilization thousands of years in the future, in which superluminal travel is im

This novel, and the prequel A Deepness in the Sky, depict a human interstellar civilization thousands of years in the future, in which superluminal travel is impossible (for the humans), so travelers use hibernation to pass the decades while their ships travel between systems. Merchants, including the ones the book portrays, often revisit systems after a century or two, so see great changes in each visit. <spoiler>The merchants repeatedly find that once smart dust (tiny swarms of nanomachines) are developed, governments inevitably use them for ubiquitous surveillance, which inevitably causes societal collapse.<https://blog.regehr.org/archives/255 https://blog.regehr.org/archives/255></spoiler> People always talk about the future Usenet and such, but this is the most important single insight of Vinge in the two books.