start from scratch

[michielbdejong]

• [ ] respond with ACK or REJECT to ADD
• [ ] update ledger when ADD is sent or received and responded to with ACK
• [ ] implement ddcd-dfs from scratch
• [ ] update whitepaper to document message types etc. for version 0.7

[michielbdejong]

* ADD
  * msgType 'ADD'
  * msgId (integer)
  --------
  * entry
    * beneficiary (you/me)
    * amount (integer)
    * unit (string)

* COND
  * msgType 'COND'
  --------
  * condition (256 bits)
  * entry
    * beneficiary (you/me)
    * amount (integer)
    * unit (string)

* FULFILL
  * msgType 'FULFILL'
  * msgId (integer)
  --------
  * condition (see above)
  * preimage (256 bits)

* ack ledger entry
  * msgType 'ACK'
  * msgId from ADD or FULFILL (integer)
  -------

* reject ledger entry
  * msgType 'REJECT'
  * msgId from ADD or FULFILL (integer)
  --------
  * reason (string, for now)

* please finalize cond
  * msgType 'PLEASE-FINALIZE'
  * condition of the COND (256 bits)
  --------
  * reason (string, for now)

* reject cond
  * msgType 'REJECT-COND'
  * condition of the COND (256 bits)
  --------
  * reason (string, for now)

ADD> <ACK

ADD> <REJECT

COND> [>PLEASE-FINALIZE]* <FULFILL >ACK

COND> [>PLEASE-FINALIZE]* <FULFILL >REJECT

COND> [>PLEASE-FINALIZE]* <REJECT-COND

COND> [>PLEASE-FINALIZE]* <REJECT-COND

Communication rules:

• you need a channel where there is never confusion about what was sent, by whom, and in which order that peer sent its messages, unless the link went down in that direction and no further messages were ever delivered.
• it's ok if messages cross each other, and in that case, it could be that an entry is rejected due to insufficient funds (which in the peer's view, haven't arrived yet) and does go through on retry.
• each peer assigns their own sequence of msgId's, starting at 0. The state of the ledger is defined by the tuple of both highest msgId's, and entries should be stored along with the sender (may be the beneficiary or not) and the msgId.

[michielbdejong]

reused the existing demo page and combined with SNAP/BTP architecture from ilp-with-accounting. Next todo: ddcd-dfs

[michielbdejong]

meant to merge this.