RippleState

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A RippleState ledger entry represents a trust line between two accounts. Each account can change its own limit and other settings, 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 and is automatically deleted.

High vs. Low Account

There can only be one RippleState entry per currency for any given pair of accounts. Since no account is privileged in the XRP Ledger, a RippleState entry 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 entry 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 RippleState 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,
    "index": "9CA88CDEDFF9252B3DE183CE35B038F57282BC9503CDFA1923EF9A95DF0D6F7B"
}

RippleState Fields

In addition to the common fields, RippleState entries have the following fields:

RippleState Flags

RippleState entries can have the following flags combined into the Flags field:

The two accounts connected by the trust line can each change their own settings with a TrustSet transaction.

RippleState Reserve

A RippleState entry counts as one item towards the owner reserve of one or both of the accounts it connects. In typical cases, the holder of a token owes a reserve and the issuer of the token does not.

Specifically, the entry counts towards an account's reserve if that account modifies a trust line to put it in a non-default state. The lsfLowReserve and lsfHighReserve flags indicate which account(s) are responsible for the owner reserve. The protocol 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:

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 entries. 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.

The XRP Ledger 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. When an account modifies a trust line, the protocol 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 entry 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)