ADSB V0 and V1 vs ADSB-V2
The U.S./Mexico mandates and the E.U. mandate define requirements to support current and planned ADS-B applications in these regions. The U.S./Mexico mandates require ADS-B Version 2 and define 19 parameters required to provide the data necessary for current and planned services, including ATC separation service. The E.U. mandate also requires ADS-B Version 2.
The E.U. mandate requires five parameters that are not part of the U.S./Mexico mandates (three of which are conditional on the actual availability of the data onboard the aircraft). The U.S./Mexico mandates require one parameter that is not part of the E.U. mandate. These differences are consistent with the current differences in surveillance requirements between the U.S./Mexico and the E.U.
2.2.2 Other countries using ADS-B for ATC separation services, such as Canada, Australia, and many countries in the ICAO Asia-Pacific region, are using ADS-B Out to provide surveillance services in mostly low-density airspace for ATC separation, or as support for existing secondary surveillance radar services in higher density en route and terminal airspace.
The needs of these nations are generally oriented towards delivery of existing levels of ATC surveillance service in new locations at low cost using existing avionics installations rather than aiming at a generational paradigm shift. Some of these countries use ADS-B for 3.0 nm separation in terminal areas.
These countries may transition to more demanding ADS-B requirements over time as their fleets and airspace requirements change.
2.2.3 These implementations accept the legacy ADS-B standards, ADS-B Version 0 and 1, which have a different and smaller set of the ADS-B Out parameters.
Other parameters are shown in the appendix
https://www.icao.int/NACC/Documents/...DSBIMPIP02.pdf
there is another thread on PPRUNE somewhere that discusses the differences in ADSB V0, V1, and V2...there was also a presentation from Honeywell on the subject.