github.com/decred/dcrd/chaincfg/v3 (go): Package chaincfg defines chain configuration parameters.  In addition to the main Decred network, which is intended for the transfer of monetary value, there also exists two currently active standard networks: regression test and testnet (version 0).  These networks are incompatible with each other (each sharing a different genesis block) and software should handle errors where input intended for one network is used on an application instance running on a different network.  For main packages, a (typically global) var may be assigned the address of one of the standard Param vars for use as the application's "active" network. When a network parameter is needed, it may then be looked up through this variable (either directly, or hidden in a library call).  If an application does not use one of the standard Decred networks, a new Params struct may be created which defines the parameters for the non-standard network.  As a general rule of thumb, all network parameters should be unique to the network, but parameter collisions can still occur.
Keywords: blockchain|cryptocurrency|dcrd|decred|decred-daemon|decred-nodes|go|golang|p2p|peer-to-peer