It is zero-coupon because there is only one cash flow at the maturity of the swap, without any intermediate coupon. It is called a swap because at maturity, one counterparty pays a fixed amount to the other in exchange for a floating amount (in this case linked to inflation). The final cash flow will therefore consist of the difference between the fixed amount and the value of the floating amount at expiry of the swap.
Detailed flows
At time = M years
Party B pays Party A the fixed amount
Party A pays Party B the floating amount
where:
is the contract fixed rate
the contract nominal value
the number of years
is the start date
is the maturity date (end of the swap)
is the inflation consumer price index at start date (time )
is the inflation consumer price index at maturity date (time )