TomP2P (https://tomp2p.net/) is a library handling firewall / UPNP support, however, the focus is academic/experimental.
TomP2P is mature enough to run in an closed environment (easy network conditions). We are currently working on making it run (relaying, NAT, UPNP) stable in the Internet.
I'm the author of TomP2P. We are currently working on integrating bitcoins for registration to make Sybil attacks much harder: https://github.com/tomp2p/TomP2P/tree/bitcoin
TomP2P (https://tomp2p.net/) is a library handling firewall / UPNP support, however, the focus is academic/experimental.
TomP2P is mature enough to run in an closed environment (easy network conditions). We are currently working on making it run (relaying, NAT, UPNP) stable in the Internet.
I'm the author of TomP2P. We are currently working on integrating bitcoins for registration to make Sybil attacks much harder: https://github.com/tomp2p/TomP2P/tree/bitcoin