Module identity 

Strongly-typed 32-byte identity newtypes for the deCDN wire protocol.

NodeId (a 32-byte Ed25519 public key) and ContentHash (a 32-byte BLAKE3 content address) are distinct types even though both wrap [u8; 32]. Keeping them distinct turns a class of confusion — passing a content hash where a node id is expected, or treating a wire-provided id as an authenticated one — into a compile error rather than a silent logic bug (see the routing-table-poisoning class behind ADR 022 §STORE Flow).

Wire compatibility

Both newtypes are #[repr(transparent)] + #[serde(transparent)], so they lay out and (de)serialize byte-for-byte identically to a bare [u8; 32]. Postcard sees the same 32 raw bytes — no discriminant moves, no ALPN bump. nodeid_postcard_identical_to_array pins this invariant.

Trust boundary

A plain NodeId is freely constructible from wire bytes by design: Kademlia legitimately learns peer ids from FindNode responses and inserts them as probe candidates. The authenticated-identity boundary is enforced one layer up by decdn_node::dht::AuthenticatedNodeId, which can only be minted from a live QUIC connection’s remote_id().

Structs

ContentHash

A 32-byte content address (BLAKE3 hash).

NodeId

A 32-byte node identifier (Ed25519 public key).

Constants

ID_LEN

Length in bytes of a NodeId or ContentHash — the size of both an Ed25519 public key and a BLAKE3 digest.