A VIX index tracks the volatility of an underlying index. In this case an index of an average of bitcoin prices, which are traded on different exchanges. For this measure option prices are used to find a gauge for volatility implied by the market. So this VIX index is tradable using these same bitcoin options.
The Bitcoin VIX we calculate is constructed by using option strike prices of the most actively traded expiries on Deribit. These expiries are the biweekly and monthly maturities from the calculation date. The Bitcoin VIX we construct is therefore equivalent to the 14 days expected volatility of the Bitcoin index, and derived from real-time, mid-quote prices of Deribit bitcoin at-the-money call and put options.