The following are some key parameters that affect the Cardano Protocol.
The “d” Parameter, which stands for decentralization, is a parameter that can be tuned to control how many blocks are produced by independent pools and how many blocks can be produced by the federation of nodes. As of March 31st, 2021, and start of Epoch 257 the d parameter will be set at zero meaning 100% of blocks are produced by independent nodes.
The “k” Parameter is a saturation parameter designed to limit the amount of stake per stake pool. Having a saturation parameter allows for greater decentralization of the network by limiting how much stake any one stake pool can have. There is a tendency for pool operators to start more pools when the k value increases and there is debate on how to limit the extent.
The “a0” Parameter pertains to the pledging mechanism of pool operators. The more pledge a stake pool has the greater the chance the pool will have to create blocks. Knowing this, delegators are incentivized to stake with pools with higher pledge. Having a higher pledge in stake pools is healthy for the network and creates safety from 51% attack since you would need to control a large number of pools with a large amount of total pledge.