In the absence of standardization, it is important to get community review on a proposal to improve its engineering quality. Community review is strongly recommended prior to registration. Registration serves a two-fold purpose. First it prevents use of the same name for different purposes, and second it provides a one-stop list which can be used to locate existing extensions or dataset classes to prevent duplicate work. The IANA registry of these codes is listed here.
Several protocols deal with multiple address families.
The 16-bit assignments are listed here. The assigned values for these parameters are listed here. AS Numbers can be obtained from the regirstry in your region. Listed below are the allocated blocks to the regional registries. Building Blocks C Capability Codes Character Set Info Directory includes detailed applications of chracter sets.