Uninstall Virtual App Protocol¶

This is the Uninstall Virtual App Protocol.

Roles¶

Three users run the protocol. They are designated as initiator, responder, and intermediary. It is required that initiator and responder have run the install-virtual-app protocol previously with the same intermediary; however it is allowed to swap the roles of initiator and responder.

The `UninstallVirtualAppParams` type¶

Field	type	description
`initiatorXpub`	`xpub`	xpub of `initiator`
`responderXpub`	`xpub`	xpub of `responder`
`intermediaryXpub`	`xpub`	xpub of `intermediary`
`targetAppIdentityHash`	`bytes32`	app identity hash of app instance to uninstall
`initiatorBalanceIncrement`	`uint256`	`initiator`'s resulting share of the installed application
`responderBalanceIncrement`	`uint256`	`responder`'s resulting share of the installed application

At the end of this protocol the commitments {left,right}ETHVirtualAppAgreement defined in the install-virtual-app protocol are cancelled, and the free balances are updated.

Commitments¶

lockCommitment¶

The protocol produces a commitment to call setState with the final state of the TimeLockedPassThrough AppInstance in the defaultOutcome parameter and the switchesOutcomeAt value at 0. This specific commitment is what guarantees that the “final outcome” of the virtual app is what is set inside of the defaultOutcome field; thereby “locking” it at this outcome.

uninstallLeft¶

A commitment to cancel the leftETHVirtualAppAgreement commitment produced by install-virtual-app and simultaneously update the free balance in the initiator-intermediary free balance.

uninstallRight¶

A commitment to cancel the rightETHVirtualAppAgreement commitment produced by install-virtual-app and simultaneously update the free balance in the intermediary-responder free balance.

Signatures¶

Signature	Commitment	Signed By
s1	lockCommitment	`initiator`
s2	lockCommitment	`intermediary`
s3	lockCommitment	`responder`
s4	uninstallLeft	`initiator`
s5	uninstallLeft	`intermediary`
s6	uninstallright	`intermediary`
s7	uninstallright	`responder`

Messages¶

sequenceDiagram participant Initiating participant Intermediary participant Responding Initiating->>Intermediary: M1 Intermediary->>Responding: M2 Responding->>Intermediary: M3 Intermediary->>Initiating: M4 Initiating->>Intermediary: M5 Intermediary->>Responding: M6 Responding->>Intermediary: M7 Intermediary->>Initiating: M8

Message	Signatures
m1	s1
m2	s1, s2
m3	s3
m4	s3, s2
m5	s4
m6	s5
m7	s6
m8	s7

M1¶

Field	Type	Description
`protocol`	`string`	`"uninstall-virtual-app"`
`params`	`UninstallVirtualAppParams`
`toXpub`	`address`	`intermediaryAddress`
`seq`	`number`	`1`
`customData.signature`	`signature`	The S1 signature

M2¶

Field	Type	Description
`protocol`	`string`	`"uninstall-virtual-app"`
`params`	`UninstallVirtualAppParams`
`toXpub`	`address`	`responderAddress`
`seq`	`number`	`2`
`customData.signature`	`signature`	The S1 signature
`customData.signature2`	`signature`	The S2 signature

M3¶

Field	Type	Description
`protocol`	`string`	`"uninstall-virtual-app"`
`params`	`UninstallVirtualAppParams`
`toXpub`	`address`	`intermediaryAddress`
`seq`	`number`	`-1`
`customData.signature`	`signature`	The S3 signature

M4¶

Field	Type	Description
`protocol`	`string`	`"uninstall-virtual-app"`
`params`	`UninstallVirtualAppParams`
`toXpub`	`address`	`initiatorAddress`
`seq`	`number`	`-1`
`customData.signature`	`signature`	The S3 signature
`customData.signature2`	`signature`	The S2 signature

M5¶

Field	Type	Description
`protocol`	`string`	`"uninstall-virtual-app"`
`params`	`UninstallVirtualAppParams`
`toXpub`	`address`	`intermediaryAddress`
`seq`	`number`	`-1`
`customData.signature`	`signature`	The S4 signature

M6¶

Field	Type	Description
`protocol`	`string`	`"uninstall-virtual-app"`
`params`	`UninstallVirtualAppParams`
`toXpub`	`address`	`initiatorAddress`
`seq`	`number`	`-1`
`customData.signature`	`signature`	The S5 signature

M7¶

Field	Type	Description
`protocol`	`string`	`"uninstall-virtual-app"`
`params`	`UninstallVirtualAppParams`
`toXpub`	`address`	`responderAddress`
`seq`	`number`	`-1`
`customData.signature`	`signature`	The S6 signature

M8¶

Field	Type	Description
`protocol`	`string`	`"uninstall-virtual-app"`
`params`	`UninstallVirtualAppParams`
`toXpub`	`address`	`intermediaryAddress`
`seq`	`number`	`-1`
`customData.signature`	`signature`	The S7 signature