- add support go mod
- encryption switched to AES-128-GCM
- disabling encryption on empty key
- disabling encryption between nodes in same DC
- transport changed to TCP
- encryption changed to AES-256-GCM
- removed DHT
- removed NAT traversal
- transport may create many TCP connections to avoid big RTT related problems
- each node may connect via local private network in region if target node located in same region
- bootstraping and peer exchange from one or more nodes
- add OS X support
- improve network performance
- UPnP forked, translated to English and error checking improvement
- minor changes