PipeNet is also the name of the scheme independently invented by Wei Dai contemporaneously with USNRL's Onion Routing: http://www.weidai.com/pipenet.txt Onion Routing is what Tor is based on. I'm not sure if the original Tor author(s) knew about PipeNet, but I wouldn't be surprised if they were familiar.

PipeNet was conceived in 1996 (https://cryptome.org/jya/pipenet.htm), before the USNRL work was made public in 1997 (IIRC), so definitely independent, in as much as these things are ever truly independent. Both are derivative of Chaum Mixes (1979), which had become popularized as anonymous e-mail remailers in the 1990s.

P.S. Not a comment about project name clashing, just thought it would be interesting to point out. Wei Dai's PipeNet is all but forgotten these days. But I had came across it (on sci.crypt?) before stumbling on the Onion Routing web page.