Ripple State

[Source]

The RippleState object type connects two accounts in a single currency. Conceptually, a RippleState object represents two trust lines between the accounts, one from each side. Each account can change the settings for its side of the RippleState object, but the balance is a single shared value. A trust line that is entirely in its default state is considered the same as a trust line that does not exist, so rippled deletes RippleState objects when their properties are entirely default.

High vs. Low Account

There can only be one RippleState object per currency for any given pair of accounts. Since no account is privileged in Xahau, a RippleState object sorts account addresses numerically, to ensure a canonical form. Whichever address is numerically lower when decoded is deemed the "low account" and the other is the "high account". The net balance of the trust line is stored from the low account's perspective.

The "issuer" for the balance in a trust line depends on whether the balance is positive or negative. If a RippleState object shows a positive balance, the high account is the issuer. If the balance is negative, the low account is the issuer. Often, the issuer has its limit set to 0 and the other account has a positive limit, but this is not reliable because limits can change without affecting an existing balance.

Example JSON

{
    "Balance": {
        "currency": "USD",
        "issuer": "rrrrrrrrrrrrrrrrrrrrBZbvji",
        "value": "-10"
    },
    "Flags": 393216,
    "HighLimit": {
        "currency": "USD",
        "issuer": "rf1BiGeXwwQoi8Z2ueFYTEXSwuJYfV2Jpn",
        "value": "110"
    },
    "HighNode": "0000000000000000",
    "LedgerEntryType": "RippleState",
    "LowLimit": {
        "currency": "USD",
        "issuer": "rsA2LpzuawewSBQXkiju3YQTMzW13pAAdW",
        "value": "0"
    },
    "LowNode": "0000000000000000",
    "PreviousTxnID": "E3FE6EA3D48F0C2B639448020EA4F03D4F4F8FFDB243A852A0F59177921B4879",
    "PreviousTxnLgrSeq": 14090896,
    "LockCount": 1,
    "LockedBalance": {
        "currency": "USD",
        "issuer": "rsA2LpzuawewSBQXkiju3YQTMzW13pAAdW",
        "value": "10"
    }
    "index": "9CA88CDEDFF9252B3DE183CE35B038F57282BC9503CDFA1923EF9A95DF0D6F7B"
}

Fields

A RippleState object has the following fields:

Name	JSON Type	Internal Type	Required?	Description
Balance	Object	Amount	Yes	The balance of the trust line, from the perspective of the low account. A negative balance indicates that the high account holds tokens issued by the low account. The issuer in this is always set to the neutral value ACCOUNT_ONE.
Flags	Number	UInt32	Yes	A bit-map of boolean options enabled for this object.
HighLimit	Object	Amount	Yes	The limit that the high account has set on the trust line. The issuer is the address of the high account that set this limit.
HighNode	String	UInt64	Yes	(Omitted in some historical ledgers) A hint indicating which page of the high account's owner directory links to this object, in case the directory consists of multiple pages.
HighQualityIn	Number	UInt32	No	The inbound quality set by the high account, as an integer in the implied ratio HighQualityIn:1,000,000,000. As a special case, the value 0 is equivalent to 1 billion, or face value.
HighQualityOut	Number	UInt32	No	The outbound quality set by the high account, as an integer in the implied ratio HighQualityOut:1,000,000,000. As a special case, the value 0 is equivalent to 1 billion, or face value.
LedgerEntryType	String	UInt16	Yes	The value 0x0072, mapped to the string RippleState, indicates that this object is a RippleState object.
LowLimit	Object	Amount	Yes	The limit that the low account has set on the trust line. The issuer is the address of the low account that set this limit.
LowNode	String	UInt64	Yes	(Omitted in some historical ledgers) A hint indicating which page of the low account's owner directory links to this object, in case the directory consists of multiple pages.
LowQualityIn	Number	UInt32	No	The inbound quality set by the low account, as an integer in the implied ratio LowQualityIn:1,000,000,000. As a special case, the value 0 is equivalent to 1 billion, or face value.
LowQualityOut	Number	UInt32	No	The outbound quality set by the low account, as an integer in the implied ratio LowQualityOut:1,000,000,000. As a special case, the value 0 is equivalent to 1 billion, or face value.
PreviousTxnID	String	Hash256	Yes	The identifying hash of the transaction that most recently modified this object.
PreviousTxnLgrSeq	Number	UInt32	Yes	The [index of the ledger][Ledger Index] that contains the transaction that most recently modified this object.
LockCount	Number	UInt32	No	The total number of lock balances on a RippleState ledger object
LockedBalance	Object	Amount	No	The current amount of locked tokens for a specific trustline

RippleState Flags

There are several options which can be either enabled or disabled for a trust line. These options can be changed with a [TrustSet transaction][]. In the ledger, flags are represented as binary values that can be combined with bitwise-or operations. The bit values for the flags in the ledger are different than the values used to enable or disable those flags in a transaction. Ledger flags have names that begin with lsf.

RippleState objects can have the following flag values:

Flag Name	Hex Value	Decimal Value	Corresponding TrustSet Flag	Description
lsfLowReserve	0x00010000	65536	(None)	This RippleState object contributes to the low account's owner reserve.
lsfHighReserve	0x00020000	131072	(None)	This RippleState object contributes to the high account's owner reserve.
lsfLowAuth	0x00040000	262144	tfSetAuth	The low account has authorized the high account to hold tokens issued by the low account.
lsfHighAuth	0x00080000	524288	tfSetAuth	The high account has authorized the low account to hold tokens issued by the high account.
lsfLowNoRipple	0x00100000	1048576	tfSetNoRipple	The low account has disabled rippling from this trust line.
lsfHighNoRipple	0x00200000	2097152	tfSetNoRipple	The high account has disabled rippling from this trust line.
lsfLowFreeze	0x00400000	4194304	tfSetFreeze	The low account has frozen the trust line, preventing the high account from transferring the asset.
lsfHighFreeze	0x00800000	8388608	tfSetFreeze	The high account has frozen the trust line, preventing the low account from transferring the asset.

Contributing to the Owner Reserve

If an account modifies a trust line to put it in a non-default state, then that trust line counts towards the account's owner reserve. In a RippleState object, the lsfLowReserve and lsfHighReserve flags indicate which account(s) are responsible for the owner reserve. The rippled server automatically sets these flags when it modifies a trust line.

The values that count towards a trust line's non-default state are as follows:

High account responsible if...	Low account responsible if...
Balance is negative (the high account holds currency)	Balance is positive (the low account holds currency)
HighLimit is not 0	LowLimit is not 0
LowQualityIn is not 0 and not 1000000000	HighQualityIn is not 0 and not 1000000000
LowQualityOut is not 0 and not 1000000000	HighQualityOut is not 0 and not 1000000000
lsfHighNoRipple flag is not in its default state	lsfLowNoRipple flag is not in its default state
lsfHighFreeze flag is enabled	lsfLowFreeze flag is enabled

The lsfLowAuth and lsfHighAuth flags do not count against the default state, because they cannot be disabled.

The default state of the two No Ripple flags depends on the state of the lsfDefaultRipple flag in their corresponding AccountRoot objects. If Default Ripple is disabled (the default), then the default state of the lsfNoRipple flag is enabled for all of an account's trust lines. If an account enables Default Ripple, then the lsfNoRipple flag is disabled (rippling is enabled) for an account's trust lines by default.

Note: Prior to the introduction of the Default Ripple flag in rippled version 0.27.3 (March 10, 2015), the default state for all trust lines was with both No Ripple flags disabled (rippling enabled).

Fortunately, rippled uses lazy evaluation to calculate the owner reserve. This means that even if an account changes the default state of all its trust lines by changing the Default Ripple flag, that account's reserve stays the same initially. If an account modifies a trust line, rippled re-evaluates whether that individual trust line is in its default state and should contribute to the owner reserve.

RippleState ID Format

The ID of a RippleState object is the [SHA-512Half][] of the following values, concatenated in order:

• The RippleState space key (0x0072)

• The AccountID of the low account

• The AccountID of the high account

• The 160-bit currency code of the trust line(s)