Table of Contents
Since space on DDRP is a scarce resource, blob owners may wish to partition their blob space into segments and offer those segments to third parties. This PIP defines a standard format for partitioning blobs into named sub-segments called "subdomains." Note that these subdomains are distinct from any subdomains that may exist on the blob's Handshake name - the existence of a subdomain blob does not imply the existence of any additional DNS records defined on the TLD.
Blobs that contain subdomains MUST start with the magic value SUB
(0x535542).
The first 32,768 bytes of the blob (inclusive of the Magic Value) MAY contain up to 255 Subdomain Records. Subdomain Records define the human-readable names used to address each blob partition, their index, and a public key for authenticating the messages contained within the partition.
Subdomain Records are formatted as follows:
version:uint8name:[15]byteindex:uint8public_key:[33]byte
The version field represents the version of the subdomain record. Currently,
it MUST be set to 0x01.
The name field represents the subdomain itself. Subdomains MUST have at
least one character, and be encoded as valid UTF-8.
The index field represents the index value that identifies this subdomain
record. Index values are used to link messages (described in PIP-8) with
subdomain records. While not required, the index value SHOULD match the
index at which the Subdomain Record appears in the blob.
The public_key field contains a public key used to authenticate message
associated with the Subdomain Record. It MUST be set to a valid secp256k1
compressed public key if authentication is requested or all zeroes.
The second 32,768 bytes of the blob is reserved for a zlib compression dictionary. It is currently unused, and MUST be filled with zeroes.
The remainder of the blob MAY contain one or more Social Messages. See PIP-8 for more details.