Merge pull request bnb-chain#7 from binance-chain/update-slashing

Update slashing part of whitepaper

WHITEPAPER.md

@@ -256,7 +256,7 @@ Proof of Staked Authority brings in decentralization and community involvement.
 1. Token holders, including the validators, can put their tokens “**bonded**” into the stake. Token holders can **delegate** their tokens onto any validator or validator candidate, to expect it can become an actual validator, and later they can choose a different validator or candidate to **re-delegate** their tokens<sup>1</sup>.
 2. All validator candidates will be ranked by the number of bonded tokens on them, and the top ones will become the real validators.
 3. Validators can share (part of) their blocking reward with their delegators.
-4. Validators can suffer from “**Slashing**”, a punishment for their bad behaviors, such as double sign and/or instability. Such loss will be shared by their **delegators as well**.
+4. Validators can suffer from “**Slashing**”, a punishment for their bad behaviors, such as double sign and/or instability.
 5. There is an “**unbonding period**” for validators and delegators so that the system makes sure the tokens remain bonded when bad behaviors are caught, the responsible will get slashed during this period.
 
 ## Staking on BC
@@ -293,15 +293,15 @@ It is quite a serious error and very likely deliberate offense when a validator
 Anyone can submit a slash request on BC with the evidence of Double Sign of BSC, which should contain the 2 block headers with the same height and parent block, sealed by the offending validator. Upon receiving the evidence, if the BC verifies it to be valid:
 
 1. The validator will be removed from validator set by an instance BSC validator set update Cross-Chain update;
-2. The stake on the validator would be slashed by the predefined amount;
+2. A predefined amount of BNB would be slashed from the **self-delegated** BNB of the validator; Both validator and its delegators will not receive the staking rewards. 
 3. Part of the slashed BNB will allocate to the submitter’s address, which is a reward and larger than the cost of submitting slash request transaction
 4. The rest of the slashed BNB will allocate to the other validators’ custody addresses, and distributed to all delegators in the same way as blocking reward.
 
 ### Inavailability
 
 The liveness of BSC relies on everyone in the Proof of Staked Authority validator set can produce blocks timely when it is their turn. Validators can miss their turn due to any reason, especially problems in their hardware, software, configuration or network. This instability of the operation will hurt the performance and introduce more indeterministic into the system.
 
-There can be an internal smart contract responsible for recording the missed blocking metrics of each validator. Once the metrics are above the predefined threshold, the blocking reward for validator will not be relayed to BC for distribution but shared with other better validators. In such a way, the poorly-operating validator should be gradually voted out of the validator set as their delegators will receive less or none reward. If the metrics remain above another higher level of threshold, the validator will be dropped from the rotation, and this will be propagated back to BC when a Slash will happen on the validator’s staking.
+There can be an internal smart contract responsible for recording the missed blocking metrics of each validator. Once the metrics are above the predefined threshold, the blocking reward for validator will not be relayed to BC for distribution but shared with other better validators. In such a way, the poorly-operating validator should be gradually voted out of the validator set as their delegators will receive less or none reward. If the metrics remain above another higher level of threshold, the validator will be dropped from the rotation, and this will be propagated back to BC, then a predefined amount of BNB would be slashed from the **self-delegated** BNB of the validator. Both validators and delegators will not receive their staking rewards. 
 
 ###  Governance Parameters