Connection to the TCE
Once built on top of a UCI implementation, a subnet connects to the TCE to start interacting with other subnets in the ecosystem. The TCE node discovery mechanism is based on hardcoded DNS seeds which serve dynamic lists of TCE node IP addresses.
Upon connecting to TCE nodes, a subnet registers itself with the TCE. The subnet registration consists in the submission of a registration certificate, a certificate that includes the initial state of the subnet—relatively to its lifetime in the TCE—and its long-lived public key (for certificate authentication). The initial state is stored by TCE nodes to validate subsequent state transitions, while both TCE nodes and subnets save the long-lived public key to authenticate future certificates.
Interactions with other subnets
Once known to the rest of the Topos ecosystem, a subnet can start interacting with other subnets, i.e., exchanging cross-subnet transactions, by submitting certificates that comply with the specifications defined in the UCI.