Unheaded: Protocol Foundation -- A Mapped Data Bus over IPv6 Hop-by-Hop Options

The Unheaded Protocol defines a mapped data bus model that transforms IPv6 packets into addressable memory by encoding a small register file directly in the IPv6 Hop-by-Hop Options extension header. We introduce a 20-byte Monad (register file) that carries program state through the network. At each hop, a BPF program (the Shim) performs computation on the Monad. The packet itself becomes the working memory, using exponent-encoded fields to pack rich metadata into the IPv6 option while remaining fully backward-compatible with existing networks. To support programs larger than what fits in a single Monad, we introduce Wotan, a memory and I/O bus that bridges Monad computation to per-flow ring-buffer storage and external topics. This decouples the Monad (pure, 20-byte compute) from memory (Wotan's configurable data planes). This memo extends the packet format with two additional capabilities: (1) Kingdom Mode Address Reclamation, which recovers up to 224 bits of deterministic address space from IPv6 addresses within a controlled L2 fabric for use as extended computational and cryptographic registers; and (2) Post-Quantum Cryptographic Identity Binding, which cryptographically binds each service identifier in the Monad to a post-quantum keypair via the Sophia dictionary system, providing quantum-resistant authentication of per-packet metadata without increasing wire overhead. This memo defines the normative packet format, exponent-encoding scheme, per-hop processing semantics, address reclamation model, post-quantum identity binding, optional chaos injection for resilience testing, and the complete computational model (Turing- complete with memory paging).