SSU
Secure Semireliable UDP (SSU) is a transport layer, for UDP messages, that is: "secured" via end-to-end encryption, and "semireliable" via unacknowledged message retransmissions.
Like the NTCP transport, SSU provides reliable, encrypted, connection-oriented, point-to-point data transport. Unique to SSU, it also provides IP detection and NAT traversal services, including:
- Cooperative NAT/Firewall traversal using introducers
- Local IP detection by inspection of incoming packets and peer testing
- Communication of firewall status and local IP, and changes to either to NTCP
- Communication of firewall status and local IP, and changes to either, to the router and the user interface
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