Merge pull request #1831 from MarnixCroes/remove-coordination-fee

Remove coordination fee

docs/FAQ/FAQ-UseWasabi.md

@@ -758,9 +758,13 @@ The default maximum is a 43000 BTC UTXO.
 
 ### What are the fees for the coinjoin?
 
-The coinjoin coordinator sets its own fee policy for the coinjoin service provided.
+As of Wasabi version [2.2.0.0](https://github.com/WalletWasabi/WalletWasabi/releases/tag/v2.2.0.0), the Wasabi client will only participate in 
+coinjoin rounds where it only pays for the mining fees.
 
-This includes things like the mining fee, the coordination fee, no coordination fee for remixes and/or no coordination fee for UTXO amounts below a threshold etc.
+Previous versions also included the coordination fee concept, where the coordinator could charge a fee for providing the service.
+This has now been removed, so it will not participate in coinjoin rounds that charge a coordination fee.
+
+Read more [here](/using-wasabi/CoinJoin.md#fees).
 
 ### What is the anonymity set?
 

docs/glossary/Glossary-PrivacyWasabi.md

@@ -152,11 +152,6 @@ A label can be added to a coin, as a small note on who knows this coin belongs t
 Good labelling can help the user and the wallet to make better privacy conscious decisions later on when spending.
 Read more: [Why do I have to label my address](/FAQ/FAQ-UseWasabi.md#why-do-i-have-to-label-my-address)
 
-### Max Coordination Fee Rate
-
-The maximum coordination fee rate the client is willing to accept to participate into a round.
-The default value is 0.
-
 ### Max Coinjoin Mining Fee Rate
 
 The maximum mining fee rate in sat/vByte the client is willing to pay to participate into a round.

docs/using-wasabi/CoinJoin.md

@@ -66,17 +66,22 @@ Notice that it is not yet possible to coinjoin from a hardware wallet, the keys
 
 ### Fees
 
-The coinjoin coordinator sets its own fee policy for the coinjoin service provided.
+As of Wasabi version [2.2.0.0](https://github.com/WalletWasabi/WalletWasabi/releases/tag/v2.2.0.0), the Wasabi client will only participate in coinjoin rounds where it only pays for the mining fees for the blockspace it uses, like any other bitcoin transaction.
 
-Although the coordinator cannot steal money from the coinjoin participants, it could set a high mining fee rate and/or a high coordination fee. 
-This would make the participants pay a lot (unnecessarily). 
-To prevent against such behavior the Wasabi client can configure the maximum mining fee rate and the maximum coordination fee it is willing to pay per round. 
-If one of these is higher than the set values, the client will not participate in the coinjoin.
+The coordinator sets the mining fee rate for the coinjoin transaction.
 
-The default is a coordination fee rate of 0 and a maximum mining fee rate of 150 sat/vByte.
+Users can set the maximum coinjoin mining fee rate they are willing to pay, as well as the minimum number of inputs the coinjoin transaction should have to participate.
+
+The default is a maximum mining fee rate of 150 sat/vByte and a minimum input count of 21.
 
 ![Coinjoin Configurations](/SettingsCoinjoinConfigs.png "Coinjoin Configurations")
 
+It will not participate in rounds where the coordinator charges a coordination fee.
+
+> Previous versions also included the coordination fee concept, where the coordinator could charge a fee for providing the service.
+This has now been removed, as it could be abused by malicious coordinators and/or would require some trust in the coordinator (like free remixes, as they are not enforced in the protocol).
+The full explanation can be found [here](https://blog.wasabiwallet.io/killing-coordination-fee/). 
+
 ## WabiSabi protocol step-by-step
 
 WabiSabi protocol requires 5 steps to successfully create and broadcast a coinjoin transaction to the bitcoin network.

docs/using-wasabi/StartupParameters.md

@@ -47,7 +47,6 @@ All configuration options available via the `Config.json` file are also availabl
 | "DustThreshold": "0.00005" | --dustthreshold=0.00005 | WASABI-DUSTTHRESHOLD=0.00005 |
 | "EnableGpu": true | --enablegpu=true | WASABI-ENABLEGPU=true |
 | "CoordinatorIdentifier": "CoinJoinCoordinatorIdentifier" | --coordinatoridentifier="coinjoincoordinatoridentifier" | WASABI-COORDINATORIDENTIFIER="coinjoincoordinatoridentifier" |
-| "MaxCoordinationFeeRate": 0.0 | --maxcoordinationfeerate=0.0 | WASABI-MAXCOORDINATIONFEERATE=0.0 |
 | "MaxCoinJoinMiningFeeRate": 150.0 | --maxcoinjoinminingfeerate=150.0 | WASABI-MAXCOINJOINMININGFEERATE=150.0 |
 | "AbsoluteMinInputCount": 21 | --absolutemininputcount=21 | WASABI-ABSOLUTEMININPUTCOUNT=21 |