The Ledger

The XRP Ledger is a shared, global ledger that is open to all. Individual participants can trust the integrity of the ledger without having to trust any single institution to manage it. The rippled server software accomplishes this by managing a ledger database that can only be updated according to very specific rules. Each instance of rippled keeps a full copy of the ledger, and the peer-to-peer network of rippled servers distributes candidate transactions among themselves. The consensus process determines which transactions get applied to each new version of the ledger. See also: The Consensus Process.

Diagram: Each ledger is the result of applying transactions to the previous ledger version.

The shared global ledger is actually a series of individual ledgers, or ledger versions, which rippled keeps in its internal database. Every ledger version has a ledger index which identifies the order in which ledgers occur. Each closed ledger version also has an identifying hash value, which uniquely identifies the contents of that ledger. At any given time, a rippled instance has an in-progress "current" open ledger, plus some number of closed ledgers that have not yet been approved by consensus, and any number of historical ledgers that have been validated by consensus. Only the validated ledgers are certain to be correct and immutable.

A single ledger version consists of several parts:

Diagram: A ledger has transactions, a state node, and a header with the close time and validation info

  • A header - The ledger index, hashes of its other contents, and other metadata.
  • A transaction tree - The transactions that were applied to the previous ledger to make this one. Transactions are the only way to change the ledger.
  • A state tree - All the ledger nodes that contain the settings, balances, and objects in the ledger as of this version.

Tree Format

As its name might suggest, a ledger's state tree is a tree data structure, with each node identified by a 256-bit value called an index. In JSON, a ledger node's index value is represented as a 64-character hexadecimal string like "193C591BF62482468422313F9D3274B5927CA80B4DD3707E42015DD609E39C94". Every node in the state tree has an index that you can use as a key to look up the node in the state tree; every transaction has an indentifying hash that you can use to look up the transaction in the transaction tree. Do not confuse the index (key) of a ledger node with the ledger_index (sequence number) of a ledger.

In the case of transactions, the identifying hash is based on the signed transaction instructions, but the contents of the transaction object when you look it up also contain the results and metadata of the transaction, which are not taken into account when generating the hash.

In the case of state nodes, rippled usually includes the index of the node along with its contents. However, the index itself is not part of the contents. The index is derived by hashing important contents of the node, along with a namespace identifier. The ledger node type determines which namespace identifier to use as well as which contents to include in the hash. This ensures every index is unique. For a hash function, rippled uses SHA-512 and then truncates the result to the first 256 bytes. This algorithm, informally called SHA-512Half, provides an output that has comparable security to SHA-256, but runs faster on 64-bit processors.

Diagram: rippled uses SHA-512Half to generate indexes for ledger nodes. The space key prevents indexes for different node types from colliding.

Header Format

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Every ledger version has a unique header that describes the contents. You can look up a ledger's header information with the ledger command. The contents of the ledger header are as follows:

Field JSON Type Internal Type Description
ledger_index String UInt32 The sequence number of the ledger. Some API methods display this as a quoted integer; some display it as a native JSON number.
ledger_hash String Hash256 The SHA-512Half of the ledger header, excluding the ledger_hash itself. This serves as a unique identifier for this ledger and all its contents.
account_hash String Hash256 The SHA-512Half of this ledger's state tree information.
close_time Number UInt32 The approximate time this ledger closed, as the number of seconds since the Ripple Epoch of 2000-01-01 00:00:00. This value is rounded based on the close_time_resolution, so later ledgers can have the same value.
closed Boolean bool If true, this transaction is no longer accepting new transactions. (However, unless this ledger is validated, it might be replaced by a different ledger with a different set of transactions.)
parent_hash String Hash256 The ledger_hash value of the previous ledger that was used to build this one. If there are different versions of the previous ledger index, this indicates from which one the ledger was derived.
total_coins String UInt64 The total number of drops of XRP owned by accounts in the ledger. This omits XRP that has been destroyed by transaction fees. The actual amount of XRP in circulation is lower because some accounts are "black holes" whose keys are not known by anyone.
transaction_hash String Hash256 The SHA-512Half of the transactions included in this ledger.
close_time_resolution Number Uint8 An integer in the range [2,120] indicating the maximum number of seconds by which the close_time could be rounded.
closeFlags (Omitted) UInt8 A bit-map of flags relating to the closing of this ledger.

Ledger Index

A ledger index is a 32-bit unsigned integer used to identify a ledger. The ledger index is also known as the ledger's sequence number. The very first ledger was ledger index 1, and each new ledger has a ledger index 1 higher than that of the ledger immediately before it.

The ledger index indicates the order of the ledgers; the Hash value identifies the exact contents of the ledger. Two ledgers with the same hash are always the same. For validated ledgers, hash values and sequence numbers are equally valid and correlate 1:1. However, this is not true for in-progress ledgers:

  • Two different rippled servers may have different contents for a current ledger with the same ledger index, due to latency in propagating transactions throughout the network.
  • There may be multiple closed ledger versions competing to be validated by consensus. These ledger versions have the same sequence number but different contents (and different hashes). Only one of these closed ledgers can become validated.
  • A current ledger's contents change over time, which would cause its hash to change, even though its ledger index number stays the same. The hash of a ledger is not calculated until the ledger is closed.

Close Flags

The ledger has only one flag defined for closeFlags: sLCF_NoConsensusTime (value 1). If this flag is enabled, it means that validators had different close times for the ledger, but built otherwise the same ledger, so they declared consensus while "agreeing to disagree" on the close time. In this case, the consensus ledger version contains a close_time value that is 1 second after that of the previous ledger. (In this case, there is no official close time, but the actual real-world close time is probably 3-6 seconds later than the specified close_time.)

The closeFlags field is not included in any JSON representations of a ledger, but is included in the binary representation of a ledger, and is one of the fields that determine the ledger's hash.

Ledger Node Types

There are several different kinds of nodes that can appear in the ledger's state tree:

Each ledger node consists of several fields. In the peer protocol that rippled servers use to communicate with each other, ledger nodes are represented in their raw binary format. In other rippled APIs, ledger nodes are represented as JSON objects.

AccountRoot

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The AccountRoot node type describes a single account object. Example AccountRoot node:

{
    "Account": "rf1BiGeXwwQoi8Z2ueFYTEXSwuJYfV2Jpn",
    "AccountTxnID": "0D5FB50FA65C9FE1538FD7E398FFFE9D1908DFA4576D8D7A020040686F93C77D",
    "Balance": "148446663",
    "Domain": "6D64756F31332E636F6D",
    "EmailHash": "98B4375E1D753E5B91627516F6D70977",
    "Flags": 8388608,
    "LedgerEntryType": "AccountRoot",
    "MessageKey": "0000000000000000000000070000000300",
    "OwnerCount": 3,
    "PreviousTxnID": "0D5FB50FA65C9FE1538FD7E398FFFE9D1908DFA4576D8D7A020040686F93C77D",
    "PreviousTxnLgrSeq": 14091160,
    "Sequence": 336,
    "TransferRate": 1004999999,
    "index": "13F1A95D7AAB7108D5CE7EEAF504B2894B8C674E6D68499076441C4837282BF8"
}

The AccountRoot node has the following fields:

Field JSON Type Internal Type Description
LedgerEntryType String UInt16 The value 0x61, mapped to the string AccountRoot, indicates that this node is an AccountRoot object.
Account String AccountID The identifying address of this account, such as rf1BiGeXwwQoi8Z2ueFYTEXSwuJYfV2Jpn.
Flags Number UInt32 A bit-map of boolean flags enabled for this account.
Sequence Number UInt32 The sequence number of the next valid transaction for this account. (Each account starts with Sequence = 1 and increases each time a transaction is made.)
Balance String Amount The account's current XRP balance in drops, represented as a string.
OwnerCount Number UInt32 The number of objects this account owns in the ledger, which contributes to its owner reserve.
PreviousTxnID String Hash256 The identifying hash of the transaction that most recently modified this node.
PreviousTxnLgrSeq Number UInt32 The index of the ledger that contains the transaction that most recently modified this node.
AccountTxnID String Hash256 (Optional) The identifying hash of the transaction most recently submitted by this account.
RegularKey String AccountID (Optional) The address of a keypair that can be used to sign transactions for this account instead of the master key. Use a SetRegularKey transaction to change this value.
EmailHash String Hash128 (Optional) The md5 hash of an email address. Clients can use this to look up an avatar through services such as Gravatar.
WalletLocator String Hash256 (Optional) DEPRECATED. Do not use.
WalletSize Number UInt32 (Optional) DEPRECATED. Do not use.
MessageKey String VariableLength (Optional) A public key that may be used to send encrypted messages to this account. In JSON, uses hexadecimal. No more than 33 bytes.
TickSize Number UInt8 (Optional) How many significant digits to use for exchange rates of Offers involving currencies issued by this address. Valid values are 3 to 15, inclusive. (Requires the TickSize amendment.)
TransferRate Number UInt32 (Optional) A transfer fee to charge other users for sending currency issued by this account to each other.
Domain String VariableLength (Optional) A domain associated with this account. In JSON, this is the hexadecimal for the ASCII representation of the domain.

AccountRoot Flags

There are several options which can be either enabled or disabled for an account. These options can be changed with an AccountSet 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.

AccountRoot nodes can have the following flag values:

Flag Name Hex Value Decimal Value Description Corresponding AccountSet Flag
lsfPasswordSpent 0x00010000 65536 Indicates that the account has used its free SetRegularKey transaction. (None)
lsfRequireDestTag 0x00020000 131072 Requires incoming payments to specify a Destination Tag. asfRequireDest
lsfRequireAuth 0x00040000 262144 This account must individually approve other users for those users to hold this account's issuances. asfRequireAuth
lsfDisallowXRP 0x00080000 524288 Client applications should not send XRP to this account. Not enforced by rippled. asfDisallowXRP
lsfDisableMaster 0x00100000 1048576 Disallows use of the master key to sign transactions for this account. asfDisableMaster
lsfNoFreeze 0x00200000 2097152 This address cannot freeze trust lines connected to it. Once enabled, cannot be disabled. asfNoFreeze
lsfGlobalFreeze 0x00400000 4194304 All assets issued by this address are frozen. asfGlobalFreeze
lsfDefaultRipple 0x00800000 8388608 Enable rippling on this addresses's trust lines by default. Required for issuing addresses; discouraged for others. asfDefaultRipple

AccountRoot Index Format

The index of an AccountRoot node is the SHA-512Half of the following values put together:

  • The Account space key (a)
  • The AccountID of the account

DirectoryNode

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The DirectoryNode node type provides a list of links to other nodes in the ledger's state tree. A single conceptual Directory takes the form of a doubly linked list, with one or more DirectoryNode objects each containing up to 32 indexes of other nodes. The first node is called the root of the directory, and all nodes other than the root node can be added or deleted as necessary.

There are two kinds of Directories:

  • Owner directories list other nodes owned by an account, such as RippleState or Offer nodes.
  • Offer directories list the offers available in the distributed exchange. A single Offer Directory contains all the offers that have the same exchange rate for the same issuances.

Example Directories:

{
    "ExchangeRate": "4F069BA8FF484000",
    "Flags": 0,
    "Indexes": [
        "AD7EAE148287EF12D213A251015F86E6D4BD34B3C4A0A1ED9A17198373F908AD"
    ],
    "LedgerEntryType": "DirectoryNode",
    "RootIndex": "1BBEF97EDE88D40CEE2ADE6FEF121166AFE80D99EBADB01A4F069BA8FF484000",
    "TakerGetsCurrency": "0000000000000000000000000000000000000000",
    "TakerGetsIssuer": "0000000000000000000000000000000000000000",
    "TakerPaysCurrency": "0000000000000000000000004A50590000000000",
    "TakerPaysIssuer": "5BBC0F22F61D9224A110650CFE21CC0C4BE13098",
    "index": "1BBEF97EDE88D40CEE2ADE6FEF121166AFE80D99EBADB01A4F069BA8FF484000"
}
{
    "Flags": 0,
    "Indexes": [
        "AD7EAE148287EF12D213A251015F86E6D4BD34B3C4A0A1ED9A17198373F908AD",
        "E83BBB58949A8303DF07172B16FB8EFBA66B9191F3836EC27A4568ED5997BAC5"
    ],
    "LedgerEntryType": "DirectoryNode",
    "Owner": "rpR95n1iFkTqpoy1e878f4Z1pVHVtWKMNQ",
    "RootIndex": "193C591BF62482468422313F9D3274B5927CA80B4DD3707E42015DD609E39C94",
    "index": "193C591BF62482468422313F9D3274B5927CA80B4DD3707E42015DD609E39C94"
}
Name JSON Type Internal Type Description
LedgerEntryType Number UInt16 The value 0x64, mapped to the string DirectoryNode, indicates that this node is part of a Directory.
Flags Number UInt32 A bit-map of boolean flags enabled for this directory. Currently, the protocol defines no flags for DirectoryNode objects.
RootIndex Number Hash256 The index of root node for this directory.
Indexes Array Vector256 The contents of this Directory: an array of indexes to other nodes.
IndexNext Number UInt64 (Optional) If this Directory consists of multiple pages, this index links to the next node in the chain, wrapping around at the end.
IndexPrevious Number UInt64 (Optional) If this Directory consists of multiple pages, this index links to the previous node in the chain, wrapping around at the beginning.
Owner String AccountID (Owner Directories only) The address of the account that owns the objects in this directory.
ExchangeRate Number UInt64 (Offer Directories only) DEPRECATED. Do not use.
TakerPaysCurrency String Hash160 (Offer Directories only) The currency code of the TakerPays amount from the offers in this directory.
TakerPaysIssuer String Hash160 (Offer Directories only) The issuer of the TakerPays amount from the offers in this directory.
TakerGetsCurrency String Hash160 (Offer Directories only) The currency code of the TakerGets amount from the offers in this directory.
TakerGetsIssuer String Hash160 (Offer Directories only) The issuer of the TakerGets amount from the offers in this directory.

Directory Index Formats

There are three different formulas for creating the index of a DirectoryNode, depending on whether the DirectoryNode represents:

  • The first page (also called the root) of an Owner Directory,
  • The first page of an Offer Directory, or
  • Later pages of either type

The first page of an Owner Directory has an index that is the SHA-512Half of the following values put together:

  • The Owner Directory space key (O, capital letter O)
  • The AccountID from the Owner field.

The first page of an Offer Directory has a special index: the higher 192 bits define the order book, and the remaining 64 bits define the exchange rate of the offers in that directory. (An index is big-endian, so the book is in the more significant bits, which come first, and the quality is in the less significant bits which come last.) This provides a way to iterate through an order book from best offers to worst. Specifically: the first 192 bits are the first 192 bits of the SHA-512Half of the following values put together:

  • The Book Directory space key (B)
  • The 160-bit currency code from the TakerPaysCurrency
  • The 160-bit currency code from the TakerGetsCurrency
  • The AccountID from the TakerPaysIssuer
  • The AccountID from the TakerGetsIssuer

The lower 64 bits of an Offer Directory's index represent the TakerPays amount divided by TakerGets amount from the offer(s) in that directory as a 64-bit number in the XRP Ledger's internal amount format.

If the DirectoryNode is not the first page in the Directory (regardless of whether it is an Owner Directory or an Offer Directory), then it has an index that is the SHA-512Half of the following values put together:

  • The Directory Node space key (d)
  • The index of the root DirectoryNode
  • The page number of this node. (Since 0 is the root DirectoryNode, this value is an integer 1 or higher.)

Escrow

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(Requires the Escrow Amendment.)

The Escrow node type represents a held payment of XRP waiting to be executed or canceled. An EscrowCreate transaction creates an Escrow node in the ledger. A successful EscrowFinish or EscrowCancel transaction deletes the node. If the Escrow node has a crypto-condition, the payment can only succeed if an EscrowFinish transaction provides the corresponding fulfillment that satisfies the condition. (The only supported crypto-condition type is PREIMAGE-SHA-256.) If the Escrow node has a FinishAfter time, the held payment can only execute after that time.

An Escrow node is associated with two addresses:

  • The owner, who provides the XRP when creating the Escrow node. If the held payment is canceled, the XRP returns to the owner.
  • The destination, where the XRP is paid when the held payment succeeds. The destination can be the same as the owner.

Example Escrow node:

{
    "Account": "rf1BiGeXwwQoi8Z2ueFYTEXSwuJYfV2Jpn",
    "Amount": "10000",
    "CancelAfter": 545440232,
    "Condition": "A0258020A82A88B2DF843A54F58772E4A3861866ECDB4157645DD9AE528C1D3AEEDABAB6810120",
    "Destination": "ra5nK24KXen9AHvsdFTKHSANinZseWnPcX",
    "DestinationTag": 23480,
    "FinishAfter": 545354132,
    "Flags": 0,
    "LedgerEntryType": "Escrow",
    "OwnerNode": "0000000000000000",
    "PreviousTxnID": "C44F2EB84196B9AD820313DBEBA6316A15C9A2D35787579ED172B87A30131DA7",
    "PreviousTxnLgrSeq": 28991004,
    "SourceTag": 11747,
    "index": "DC5F3851D8A1AB622F957761E5963BC5BD439D5C24AC6AD7AC4523F0640244AC"
}

An Escrow node has the following fields:

Name JSON Type Internal Type Description
Account String AccountID The address of the owner (sender) of this held payment. This is the account that provided the XRP, and gets it back if the held payment is canceled.
Destination String AccountID The destination address where the XRP is paid if the held payment is successful.
Amount String Amount The amount of XRP, in drops, to be delivered by the held payment.
Condition String VariableLength (Optional) A PREIMAGE-SHA-256 crypto-condition, as hexadecimal. If present, the EscrowFinish transaction must contain a fulfillment that satisfies this condition.
CancelAfter Number UInt32 (Optional) The held payment can be canceled if and only if this field is present and the time it specifies has passed. Specifically, this is specified as seconds since the Ripple Epoch and it "has passed" if it's earlier than the close time of the previous validated ledger.
FinishAfter Number UInt32 (Optional) The time, in seconds since the Ripple Epoch, after which this held payment can be finished. Any EscrowFinish transaction before this time fails. (Specifically, this is compared with the close time of the previous validated ledger.)
SourceTag Number UInt32 (Optional) An arbitrary tag to further specify the source for this held payment, such as a hosted recipient at the owner's address.
DestinationTag Number UInt32 (Optional) An arbitrary tag to further specify the destination for this held payment, such as a hosted recipient at the destination address.
OwnerNode String UInt64 A hint indicating which page of the owner directory links to this node, in case the directory consists of multiple pages. Note: The node does not contain a direct link to the owner directory containing it, since that value can be derived from the Account.
PreviousTxnID String Hash256 The identifying hash of the transaction that most recently modified this node.
PreviousTxnLgrSeq Number UInt32 The index of the ledger that contains the transaction that most recently modified this node.

Escrow Index Format

The index of an Escrow node is the SHA-512Half of the following values put together:

  • The Escrow space key (u)
  • The AccountID of the sender of the EscrowCreate transaction that created the Escrow node
  • The Sequence number of the EscrowCreate transaction that created the Escrow node

Offer

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The Offer node type describes an offer to exchange currencies, more traditionally known as an order, in the XRP Ledger's distributed exchange. An OfferCreate transaction only creates an Offer node in the ledger when the offer cannot be fully executed immediately by consuming other offers already in the ledger.

An offer can become unfunded through other activities in the network, while remaining in the ledger. However, rippled automatically prunes any unfunded offers it happens across in the course of transaction processing (and only transaction processing, because the ledger state must only be changed by transactions). For more information, see lifecycle of an offer.

Example Offer node:

{
    "Account": "rBqb89MRQJnMPq8wTwEbtz4kvxrEDfcYvt",
    "BookDirectory": "ACC27DE91DBA86FC509069EAF4BC511D73128B780F2E54BF5E07A369E2446000",
    "BookNode": "0000000000000000",
    "Flags": 131072,
    "LedgerEntryType": "Offer",
    "OwnerNode": "0000000000000000",
    "PreviousTxnID": "F0AB71E777B2DA54B86231E19B82554EF1F8211F92ECA473121C655BFC5329BF",
    "PreviousTxnLgrSeq": 14524914,
    "Sequence": 866,
    "TakerGets": {
        "currency": "XAG",
        "issuer": "r9Dr5xwkeLegBeXq6ujinjSBLQzQ1zQGjH",
        "value": "37"
    },
    "TakerPays": "79550000000",
    "index": "96F76F27D8A327FC48753167EC04A46AA0E382E6F57F32FD12274144D00F1797"
}

An Offer node has the following fields:

Name JSON Type Internal Type Description
LedgerEntryType String UInt16 The value 0x6F, mapped to the string Offer, indicates that this node is an Offer object.
Flags Number UInt32 A bit-map of boolean flags enabled for this offer.
Account String AccountID The address of the account that owns this offer.
Sequence Number UInt32 The Sequence value of the OfferCreate transaction that created this Offer node. Used in combination with the Account to identify this Offer.
TakerPays String or Object Amount The remaining amount and type of currency requested by the offer creator.
TakerGets String or Object Amount The remaining amount and type of currency being provided by the offer creator.
BookDirectory String UInt256 The index of the Offer Directory that links to this offer.
BookNode String UInt64 A hint indicating which page of the offer directory links to this node, in case the directory consists of multiple pages.
OwnerNode String UInt64 A hint indicating which page of the owner directory links to this node, in case the directory consists of multiple pages. Note: The offer does not contain a direct link to the owner directory containing it, since that value can be derived from the Account.
PreviousTxnID String Hash256 The identifying hash of the transaction that most recently modified this node.
PreviousTxnLgrSeq Number UInt32 The index of the ledger that contains the transaction that most recently modified this node.
Expiration Number UInt32 (Optional) Indicates the time after which this offer is considered unfunded. See Specifying Time for details.

Offer Flags

There are several options which can be either enabled or disabled when an OfferCreate transaction creates an offer node. 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.

Offer nodes can have the following flag values:

Flag Name Hex Value Decimal Value Description Corresponding OfferCreate Flag
lsfPassive 0x00010000 65536 The node was placed as a passive offer. This has no effect on the node in the ledger. tfPassive
lsfSell 0x00020000 131072 The node was placed as a sell offer. This has no effect on the node in the ledger (because tfSell only matters if you get a better rate than you asked for, which cannot happen after the node enters the ledger). tfSell

Offer Index Format

The index of an Offer node is the SHA-512Half of the following values put together:

  • The Offer space key (o)
  • The AccountID of the account placing the offer
  • The Sequence number of the transaction that created the offer

PayChannel

[Source]

(Requires the PayChan Amendment.)

The PayChannel node type represents a payment channel. Payment channels enable small, rapid off-ledger payments of XRP that can be later reconciled with the consensus ledger. A payment channel holds a balance of XRP that can only be paid out to a specific destination address until the channel is closed. Any unspent XRP is returned to the channel's owner (the source address that created and funded it) when the channel closes.

The PaymentChannelCreate transaction type creates a PayChannel node. The PaymentChannelFund and PaymentChannelClaim transaction types modify existing PayChannel nodes.

When a payment channel expires, at first it remains on the ledger, because only new transactions can modify ledger contents. Transaction processing automatically closes a payment channel when any transaction accesses it after the expiration. Therefore, to "finalize" the closing of an expired channel and return the unspent XRP to the owner, some address must send a new PaymentChannelClaim or PaymentChannelFund transaction accessing the channel.

Example PayChannel node:

{
    "Account": "rBqb89MRQJnMPq8wTwEbtz4kvxrEDfcYvt",
    "Destination": "rf1BiGeXwwQoi8Z2ueFYTEXSwuJYfV2Jpn",
    "Amount": "4325800",
    "Balance": "2323423",
    "PublicKey": "32D2471DB72B27E3310F355BB33E339BF26F8392D5A93D3BC0FC3B566612DA0F0A",
    "SettleDelay": 3600,
    "Expiration": 536027313,
    "CancelAfter": 536891313,
    "SourceTag": 0,
    "DestinationTag": 1002341,
    "Flags": 0,
    "LedgerEntryType": "PayChannel",
    "OwnerNode": "0000000000000000",
    "PreviousTxnID": "F0AB71E777B2DA54B86231E19B82554EF1F8211F92ECA473121C655BFC5329BF",
    "PreviousTxnLgrSeq": 14524914,
    "index": "96F76F27D8A327FC48753167EC04A46AA0E382E6F57F32FD12274144D00F1797"
}

A PayChannel node has the following fields:

Name JSON Type Internal Type Description
LedgerEntryType String UInt16 The value 0x78, mapped to the string PayChannel, indicates that this node is a payment channel object.
Account String AccountID The source address that owns this payment channel. This comes from the sending address of the transaction that created the channel.
Destination String AccountID The destination address for this payment channel. While the payment channel is open, this address is the only one that can receive XRP from the channel. This comes from the Destination field of the transaction that created the channel.
Amount String Amount Total XRP, in drops, that has been allocated to this channel. This includes XRP that has been paid to the destination address. This is initially set by the transaction that created the channel and can be increased if the source address sends a PaymentChannelFund transaction.
Balance String Amount Total XRP, in drops, already paid out by the channel. The difference between this value and the Amount field is how much XRP can still be paid to the destination address with PaymentChannelClaim transactions. If the channel closes, the remaining difference is returned to the source address.
PublicKey String PubKey Public key, in hexadecimal, of the key pair that can be used to sign claims against this channel. This can be any valid secp256k1 or Ed25519 public key. This is set by the transaction that created the channel and must match the public key used in claims against the channel. The channel source address can also send XRP from this channel to the destination without signed claims.
SettleDelay Number UInt32 Number of seconds the source address must wait to close the channel if it still has any XRP in it. Smaller values mean that the destination address has less time to redeem any outstanding claims after the source address requests to close the channel. Can be any value that fits in a 32-bit unsigned integer (0 to 2^32-1). This is set by the transaction that creates the channel.
OwnerNode String UInt64 A hint indicating which page of the source address's owner directory links to this node, in case the directory consists of multiple pages.
PreviousTxnID String Hash256 The identifying hash of the transaction that most recently modified this node.
PreviousTxnLgrSeq Number UInt32 The index of the ledger that contains the transaction that most recently modified this node.
Flags Number UInt32 A bit-map of boolean flags enabled for this payment channel. Currently, the protocol defines no flags for PayChannel nodes.
Expiration Number UInt32 (Optional) The mutable expiration time for this payment channel, in seconds since the Ripple Epoch. The channel is expired if this value is present and smaller than the previous ledger's close_time field. See Setting Channel Expiration for more details.
CancelAfter Number UInt32 (Optional) The immutable expiration time for this payment channel, in seconds since the Ripple Epoch. This channel is expired if this value is present and smaller than the previous ledger's close_time field. This is optionally set by the transaction that created the channel, and cannot be changed.
SourceTag Number UInt32 (Optional) An arbitrary tag to further specify the source for this payment channel, such as a hosted recipient at the owner's address.
DestinationTag Number UInt32 (Optional) An arbitrary tag to further specify the destination for this payment channel, such as a hosted recipient at the destination address.

Setting Channel Expiration

The Expiration field of a payment channel is the mutable expiration time, in contrast to the immutable expiration time represented by the CancelAfter field. The expiration of a channel is always considered relative to the close_time field of the previous ledger. The Expiration field is omitted when a PayChannel node is created. There are several ways the Expiration field of a PayChannel node can be updated, which can be summarized as follows: a channel's source address can set the Expiration of the channel freely as long as the channel always remains open at least SettleDelay seconds after the first attempt to close it.

Source Address

The source address can set the Expiration directly with the PaymentChannelFund transaction type. The new value must not be earlier than whichever of the following values is earliest:

  • The current Expiration value (if one is set)
  • The previous ledger's close time plus the SettleDelay of the channel

In other words, the source address can always make the Expiration later if an expiration is already set. The source can make an Expiration value earlier or set an Expiration if one isn't currently set, as long as the new value is at least SettleDelay seconds in the future. If the source address attempts to set an invalid Expiration date, the transaction fails with the temBAD_EXPIRATION error code.

The source address can also set the Expiration with the tfClose flag of the PaymentChannelClaim transaction type. If the flag is enabled, the ledger automatically sets the Expiration to whichever of the following values is earlier:

  • The current Expiration value (if one is set)
  • The previous ledger's close time plus the SettleDelay of the channel

The source address can remove the Expiration with the tfRenew flag of the PaymentChannelClaim transaction type.

Destination Address

The destination address cannot set the Expiration field. However, the destination address can use the PaymentChannelClaim's tfClose flag to close a channel immediately.

Other Addresses

If any other address attempts to set an Expiration field, the transaction fails with the tecNO_PERMISSION error code. However, if the channel is already expired, the transaction causes the channel to close and results in tesSUCCESS instead.

PayChannel Index Format

The index of a PayChannel node is the SHA-512Half of the following values put together:

  • The PayChannel space key (x)
  • The AccountID of the source account
  • The AccountID of the destination account
  • The Sequence number of the transaction that created the channel

RippleState

[Source]

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

Since no account is privileged in the XRP Ledger, a RippleState node sorts their account addresses numerically, to ensure a canonical form. Whichever address is numerically lower is deemed the "low account" and the other is the "high account".

Example RippleState node:

{
    "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"
}

A RippleState node has the following fields:

Name JSON Type Internal Type Description
LedgerEntryType String UInt16 The value 0x72, mapped to the string RippleState, indicates that this node is a RippleState object.
Flags Number UInt32 A bit-map of boolean options enabled for this node.
Balance Object Amount The balance of the trust line, from the perspective of the low account. A negative balance indicates that the low account has issued currency to the high account. The issuer in this is always set to the neutral value ACCOUNT_ONE.
LowLimit Object Amount 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.
HighLimit Object Amount 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.
PreviousTxnID String Hash256 The identifying hash of the transaction that most recently modified this node.
PreviousTxnLgrSeq Number UInt32 The index of the ledger that contains the transaction that most recently modified this node.
LowNode String UInt64 (Omitted in some historical ledgers) A hint indicating which page of the low account's owner directory links to this node, in case the directory consists of multiple pages.
HighNode String UInt64 (Omitted in some historical ledgers) A hint indicating which page of the high account's owner directory links to this node, in case the directory consists of multiple pages.
LowQualityIn Number UInt32 (Optional) The inbound quality set by the low account, as an integer in the implied ratio LowQualityIn:1,000,000,000. The value 0 is equivalent to 1 billion, or face value.
LowQualityOut Number UInt32 (Optional) The outbound quality set by the low account, as an integer in the implied ratio LowQualityOut:1,000,000,000. The value 0 is equivalent to 1 billion, or face value.
HighQualityIn Number UInt32 (Optional) The inbound quality set by the high account, as an integer in the implied ratio HighQualityIn:1,000,000,000. The value 0 is equivalent to 1 billion, or face value.
HighQualityOut Number UInt32 (Optional) The outbound quality set by the high account, as an integer in the implied ratio HighQualityOut:1,000,000,000. The value 0 is equivalent to 1 billion, or face value.

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 nodes can have the following flag values:

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

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 node, 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 NoRipple flags depends on the state of the lsfDefaultRipple flag in their corresponding AccountRoot nodes. If DefaultRipple 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 DefaultRipple, then the lsfNoRipple flag is disabled (rippling is enabled) for an account's trust lines by default. Note: Prior to the introduction of the DefaultRipple flags in rippled version 0.27.3 (March 10, 2015), the default state for all trust lines was with lsfNoRipple 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 DefaultRipple 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 the owner reserve.

RippleState Index Format

The index of a RippleState node is the SHA-512Half of the following values put together:

  • The RippleState space key (r)
  • The AccountID of the low account
  • The AccountID of the high account
  • The 160-bit currency code of the trust line(s)

SignerList

[Source]

The SignerList node type represents a list of parties that, as a group, are authorized to sign a transaction in place of an individual account. You can create, replace, or remove a SignerList using the SignerListSet transaction type This node type is introduced by the MultiSign amendment. New in: rippled 0.31.0

Example SignerList node:

{
    "Flags": 0,
    "LedgerEntryType": "SignerList",
    "OwnerNode": "0000000000000000",
    "PreviousTxnID": "5904C0DC72C58A83AEFED2FFC5386356AA83FCA6A88C89D00646E51E687CDBE4",
    "PreviousTxnLgrSeq": 16061435,
    "SignerEntries": [
        {
            "SignerEntry": {
                "Account": "rsA2LpzuawewSBQXkiju3YQTMzW13pAAdW",
                "SignerWeight": 2
            }
        },
        {
            "SignerEntry": {
                "Account": "raKEEVSGnKSD9Zyvxu4z6Pqpm4ABH8FS6n",
                "SignerWeight": 1
            }
        },
        {
            "SignerEntry": {
                "Account": "rUpy3eEg8rqjqfUoLeBnZkscbKbFsKXC3v",
                "SignerWeight": 1
            }
        }
    ],
    "SignerListID": 0,
    "SignerQuorum": 3,
    "index": "A9C28A28B85CD533217F5C0A0C7767666B093FA58A0F2D80026FCC4CD932DDC7"
}

A SignerList node has the following fields:

Name JSON Type Internal Type Description
OwnerNode String UInt64 A hint indicating which page of the owner directory links to this node, in case the directory consists of multiple pages.
SignerQuorum Number UInt32 A target number for signer weights. To produce a valid signature for the owner of this SignerList, the signers must provide valid signatures whose weights sum to this value or more.
SignerEntries Array Array An array of SignerEntry objects representing the parties who are part of this signer list.
SignerListID Number UInt32 An ID for this signer list. Currently always set to 0. If a future amendment allows multiple signer lists for an account, this may change.
PreviousTxnID String Hash256 The identifying hash of the transaction that most recently modified this node.
PreviousTxnLgrSeq Number UInt32 The index of the ledger that contains the transaction that most recently modified this node.

The SignerEntries may be any combination of funded and unfunded addresses that use either secp256k1 or ed25519 keys.

SignerEntry Object

Each member of the SignerEntries field is an object that describes that signer in the list. A SignerEntry has the following fields:

Name JSON Type Internal Type Description
Account String AccountID An XRP Ledger address whose signature contributes to the multi-signature. It does not need to be a funded address in the ledger.
SignerWeight Number UInt16 The weight of a signature from this signer. A multi-signature is only valid if the sum weight of the signatures provided meets or exceeds the SignerList's SignerQuorum value.

When processing a multi-signed transaction, the server dereferences the Account values with respect to the ledger at the time of transaction execution. If the address does not correspond to a funded AccountRoot node, then only the master secret associated with that address can be used to produce a valid signature. If the account does exist in the ledger, then it depends on the state of that account. If the account has a Regular Key configured, the Regular Key can be used. The account's master key can only be used if it is not disabled. A multi-signature cannot be used as part of another multi-signature.

SignerLists and Reserves

A SignerList contributes to its owner's reserve requirement. The SignerList itself counts as two objects, and each member of the list counts as one. As a result, the total owner reserve associated with a SignerList is anywhere from 3 times to 10 times the reserve required by a single trust line (RippleState) or Offer node in the ledger.

SignerList Index Format

The index of a SignerList node is the SHA-512Half of the following values put together:

  • The RippleState space key (S)
  • The AccountID of the owner of the SignerList
  • The SignerListID (currently always 0)