# Gavin Andresen
# 2010-07-14 02:20:45
# https://bitcointalk.org/index.php?topic=286.msg2721#msg2721

@s{quotedtext}
@s{quotedtext}
I'm imagining: @p{par}

A lightweight client would have a wallet with coins in it (public+private key pairs). @p{par}

And a secure way of sending messages to, and getting messages from, any of the ultra-fast, always-connected heavyweight nodes. @p{par}

The lightweight client sends money by: @p{brk}
  creating a transaction (signing coins with the private key) @p{brk}
  sending the signed transaction securely to the ultra-fast server, which puts it on the network. @p{brk}
  receiving confirmation that the transaction was valid and sent, and updating its wallet (marks coins as spent) @p{brk}
   (or getting a "you already spent those coins" error from the server) @p{par}

The lightweight client receives money by: @p{brk}
  Either polling the server every once in a while, asking "Any payments to these BC addresses that I have in my wallet?" @p{brk}
   ... or asking the server to tell it whenever it sees a transaction to a list of BC addresses (or maybe when it sees @p{brk}
    a relevant transaction with N confirmations) @p{brk}
  When transactions occur, the lightweight client updates its wallet (adds the coins). @p{par}

You don't have to trust the server; it never has your private keys. @p{par}

Well, you do have to trust that the server doesn't lie about whether your transactions are valid or not, but why would the server lie about that? @p{par}