Off-Chain Identity

Diem Payment Network wallets benefit from consistent standards for naming and addressing across participants and their clients.

Subaddresses

Each account on-chain is represented by a 16-byte value called an account address. To allow multiplexing of a single address into distinct off-chain identities, or wallets, a participant may use a subaddress. For convenience, Diem defines a standard format for representing the combination of the an account address and a subaddress as an account identifier. Account identifiers have a dedicated URI representation including parameters called an intent identifier. Subaddresses, account identifiers, and intent identifiers are defined in DIP-5.

Subaddresses

• 8 bytes
• Unambiguous (i.e., Recipient VASPs should not issue the same subaddress to multiple clients)
• The zero subaddress (0x0000000000000000) is reserved to denote the root (VASP owned) account.
• Subaddresses should be single-use and should not be generated from personal information, such as names, email addresses, or government-issued identification numbers.

Account Identifiers

Account Identifier format: <prefix> | <delimiter> | <version> | <encoded payload> | <checksum>

• A prefix (also known as hrp (human readable part) which identifies the network version this address is intended for
  • “dm” for Mainnet addresses
  • “tdm” for Testnet addresses
  • "pdm" for Pre-Mainnet addresses
• A Bech32 delimiter: The character “1” (one)
• A Bech32 version identifier: The character “p” (version = 1) for on-chain with subaddress
• A Bech32 encoded payload: For version 1, is Diem account address + subaddress (16 + 8 bytes)
• The last 6 characters correspond to the Bech32 checksum

The Diem Account Identifier must not be mixed-cases and represented by only all upper or lower case. For example, both dm1pptdxvfjck4jyw3rkfnm2mnd2t5qqqqqqqqqqqqq305frg or DM1PPTDXVFJCK4JYW3RKFNM2MND2T5QQQQQQQQQQQQQ305FRG are valid but dm1pptdXVFJCK4JYW3RKFNM2MND2t5qqqqqqqqqqqqq305frg is not.

Example with explicit subaddress

Identifier information

• Prefix (string)
  • Network: dm
• Address type (version prefix): 01 (letter p in Bech32 alphabet)
• Address payload (in hex)
  • Address: 0xf72589b71ff4f8d139674a3f7369c69b
  • Subaddress: 0xcf64428bdeb62af2
• Checksum: 2vfufk

Account identifier: dm1p7ujcndcl7nudzwt8fglhx6wxn08kgs5tm6mz4us2vfufk

Example without explicit subaddress (root account)

Identifier information

• Prefix (string)
  • Network: dm
• Address type (version prefix): 01 (letter p in Bech32 alphabet)
• Address payload (in hex)
  • Address: 0xf72589b71ff4f8d139674a3f7369c69b
  • Subaddress: 0x0000000000000000
• Checksum: d8p9cq

Account identifier: dm1p7ujcndcl7nudzwt8fglhx6wxnvqqqqqqqqqqqqqd8p9cq

Intent identifiers

The Intent Identifier consists of

• A prefix: diem:// to explicitly specify how the identifier should be interpreted
• A base URI: account identifier
• Query parameters
  • Provides details for how the request should be fulfilled
  • Currently supported parameters:
    • currency uses the 'c' key, with the value encoded as a 3-letter currency code (ex. XDX)
    • amount uses the 'am' key, with the value encoded in micro units (10e-6)

Example: Request Intent

This intent represents a request to receive funds at a given address. Since neither the amount nor currency are prefilled, the sender will define these fields.

• Prefix: diem://
• Base URI: Account Identifier: dm1p7ujcndcl7nudzwt8fglhx6wxn08kgs5tm6mz4us2vfufk
• Query parameters: none

Intent identifier: diem://dm1p7ujcndcl7nudzwt8fglhx6wxn08kgs5tm6mz4us2vfufk

Example: Request Intent with Currency

This intent represents a request to receive funds in a specific currency at a given address. The amount is defined by the sender.

• Prefix: diem://
• Base URI: Account Identifier: dm1p7ujcndcl7nudzwt8fglhx6wxn08kgs5tm6mz4us2vfufk
• Query parameters: c=XDX (currency preference is XDX composite token)

Intent identifier: diem://dm1p7ujcndcl7nudzwt8fglhx6wxn08kgs5tm6mz4us2vfufk?c=XDX

Example: Request Intent with Currency and Amount

This intent represents a request to receive a specific amount in a specific currency for a given address.

Identifier information

• Prefix: diem://
• Base URI: Account Identifier: dm1p7ujcndcl7nudzwt8fglhx6wxn08kgs5tm6mz4us2vfufk
• Query parameters
  • c=XDX (currency preference is XDX composite token)
  • am=1000000 (for 1 XDX, amount is 1000000 µ-units)

Intent identifier: diem://dm1p7ujcndcl7nudzwt8fglhx6wxn08kgs5tm6mz4us2vfufk?c=XDX&am=1000000