Benford continues his earlier book, "The Martian Race", with this novel. If you liked the characters and logic in that book, you will probably be attracted to this. Rather didactic in parts, with schematics of, say, the heliopause at the outer solar system. These diagrams would not be out of place in a science text. Benford actively tries to educate his readers. At times this leads to dry passages in the text.
Did you know that Benford's research area is plasma physics? He parlays that expertise into envisioning vast alien intelligences that are basically sparse plasmas. A very evocative image. Along these lines, he makes a valiant effort to portray truly alien minds interacting with each other, and with humans. The effort is commendable. His aliens are not humans dressed up in funny skins, acting as aliens, which is what a lot of science fiction depictions end up as.
But I am not sure that he truly succeeds. While yes, the aliens do come across as different, I found the resultant read to be rather dull and sterile.