Author: Jeff Garzik 2015-05-12 19:38:20
Published on: 2015-05-12T19:38:20+00:00
The discussion revolves around the problem of security in blockchain networks when a small part of the chain is attacked. It is noted that an attacker can easily cause a network-wide DoS by attacking a few nodes. The discussion then moves on to the desirable characteristics for block coverage, such as having locality and uniform coverage by the network, without depending on random peers or creating vulnerability through chasing processes. It is suggested that gaps in block coverage should be handled by archive nodes, and the decision to contact a node should require O(1) communications. The expression of what blocks a node has should be compact and computationally efficient. Figuring out what block ranges a peer has given should also be computationally efficient. The communication about what blocks a node has should be compact, and the coverage created by the network should remain uniform as the blockchain grows. Growth of the blockchain should not cause much (or any) need to refetch old blocks. The proposed schemes are based on reservoir sampling or consistent hashes, which come close but fail one of the desirable characteristics. In conclusion, it is suggested that more time needs to be spent on discovering a scheme that meets all the criteria for block coverage and ensuring security in blockchain networks.
Updated on: 2023-06-09T20:51:54.282532+00:00