Beranek and BBN both make an appearance in Mitch Waldrop's excellent book "The Dream Machine," which is in theory a biography of J.C.R. Licklider (who was mentioned in the obit), but in practice a history of computing from the 1930s onward. It has been out of print for some time, but a Kindle edition just came out this summer[1]. It's a great book and worth many times the $3.99 Amazon is charging for it.
[1]. https://www.amazon.com/gp/aw/d/B01FIPHEXM