Open Collections

Moshrefi, Niusha

University of British Columbia

Full nodes in a blockchain network store and verify a copy of the whole blockchain. Unlike full nodes, light clients are low-capacity devices that want to validate cer- tain data on a blockchain. They query the data they want from a full node. If light clients do not verify the data they receive, full nodes might deceive them. SPV, introduced in the Bitcoin white paper, is a practical solution to this problem cur- rently used in many PoW blockchains. In SPV, the resources needed to verify a full node’s response grow linearly with the blockchain size, making it inefficient over the long run. Another issue with SPV is that the full nodes do not get compensated for the services they provide. In this work, we introduce LIGHTSYNC, a simple and cost-effective solution for light clients to verify the inclusion of certain data in a PoW blockchain. LIGHT- SYNC enjoys a number of salient features. First, the resources needed for running LIGHTSYNC remain constant no matter what the size of the blockchain is. Sec- ond, LIGHTSYNC is provably secure under the variable difficulty settings. Third, LIGHTSYNC can be implemented without the need for any excess built-in struc- ture.

Text

2022-12-01

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/83333

Electrical Engineering

University of British Columbia

UBCO

http://creativecommons.org/licenses/by-nc-nd/4.0/