A client which could just send and respond ping-pong messages.
It will serve as a skeleton of a distributed ledger

Helpful links

• http://asyncio.readthedocs.io/en/latest/tcp_echo.html
• echo server / client

Notes

• peers discovery requires central registry for the first call to get the list of some peers, after that they can use gossip protocol to discover others.

Block fields

• Block number
• Previous hash
• Transactions / Payload
• Signature
• Hash

A block is considered valid if it as proof of work / stake / autority "token"/ confirmation

We need to come up with an architecture of the ledger, including:

• We need simple p2p client
• We need a synchronization protocol
• We need a transactions protocol (create new transaction, validate others transactions, add a transaction to a block, add a block to a chain)
• Every client must sign the transactions it produces, i.e have private/public gpg keypair

Each transaction should contain

• UID (which should have Proof-of-work)
• Payload
• Timestamp (can be a part of payload)

Set of transactions will be combined in a block having Merkle-tree (#1) structure.

Transaction is considered valid if it's signed by the sender

As a subtask of #2.
Before going forward we need to understand how the users will come to a consensus in the distributed p2p network.
All the research can be collected here

As a basement of the blockchain we need to implement a merkle (hash) tree

• Wiki
• Understandin merkle trees article