Now, each new block carries a hash code from the previous block. what if we devised a way that the "current" block chain of a coin was only 10 blocks deep. that covers rooting out a bad fork and the number of confirmations for most businesses. as a new block is hashed, the eleventh one back is archived and perhaps sends a hash of some kind to the new block. the new block has its own hash, the previous hash and an archived "marker" hash.
Archived where? Why would you even want to do that?
So, if I use a sybil attack, I just need to run nodes with my own 10 blocks and feed them to the victim? The victim wouldn't know if the 10 blocks is actually stem out from the network. For example, an attacker can just mine 10 blocks with low difficulty and send it to the user.
i am thinking from the hip and it might be hard, but this is wholly possible. every wallet will have the ability to pull any block from, still transparent. most sites will use the entire block chain to operate as a block explorer, but software wallets and casual use wallets simply download the last ten blocks on the first use and start working. i only see a problem with quickly locating and viewing a past tx that is older than ten blocks. querying a block is easy, just go to that block, but the daemon would have no way of knowing what block an old tx is in without accessing a specialized network node.
Sorry but you can't. Full nodes indexes the entire Blockchain and looks for transaction related to any addresses that is associated with any address in the wallet.
If you import a wallet, you will have to ask another server to give you all the information. There is an extremely HUGE problem with this. Lets go to this part then. What you are doing is rather similar to SPV clients. They download the block headers and they ask the nodes for transactions related to the address and they verify that each transaction indeed exist in the blockchain that they downloaded. If they don't do this, they will literally be blindly trust what the nodes say.
this would mean that wallet types would need to be chosen carefully to start and would vary much. assume that anyone that wants to operate a full node would need a "node" wallet and daemon and need the whole block chain. user wallets would only download and access the ten blocks. mining wallets?
![Huh](https://bitcointalk.org/Smileys/default/huh.gif)
? not sure. just a thought as we slowly evolve that original bitcoin code, both in bitcoin itself and in new coins/tokens
Not a new idea, still not possible. If you don't even download the block header, you cannot use Bitcoin without fully trusting a third party.
You don't need the full blockchain, you run a SPV wallet. End of story.
SPV wallets: Downloads the block header. Verifies that all the transaction are indeed included in the blockchain. SPV can be similar in the sense that they will still be trusting the nodes to supply them with blocks that are valid. SPV will however, only use block headers that has the LONGEST proof of work. This is harder to attack than the above.