UZP: Universal Zero-Port Transport Protocol

The Universal Zero-Port Transport Protocol (UZP) defines an identity- addressed, encrypted-by-default transport for the Universal Zero-Port Interconnect Framework (UZPIF; [UZPIF]). Instead of exposing IP:port listeners, both endpoints establish outbound, identity-bound sessions to one or more Rendezvous Nodes (RNs). The RN performs flow stitching but never terminates end-to-end cryptography or holds long- term secrets. Application data is carried over an authenticated encryption (AEAD) channel keyed by a handshake based on modern and post-quantum-capable primitives, and reliability is expressed at the block level rather than at the TCP segment or stream level. This document is part of an experimental, research-oriented Independent Stream suite. It defines the current normative baseline for trust objects, validation rules, and security semantics within its scope. Hard interoperability is expected for shared object semantics and validation rules. Full wire-level, clustering, and proof-family interoperability is not claimed everywhere yet; the remaining details are intentionally profile-defined or deferred where noted.