Public data is the market data available to all interested parties. This includes orderbook data and post trade data according to the Market model for each market.
See Appendix E in the Nasdaq Iceland Genium INET Market Model
See Appendix I in the Nasdaq Nordic INET Nordic Market Model
Private data is the the market data that is private to each market participant. This includes trader information and sometimes trading party information and various private fields on Orders (client ref, etc.)
Sigti can be configured to use either just public data or both public and private data. To see if a user has access to private data, hover over the user icon in the top right corner of the application. If a user has access to private data, the text “private data“ will we displayed
If a user has access to private data she has access to PivateOrder, PrivateTrade and PrivateTradeReport in the Tick data and has access to Alarms from alert that are based on private data.