"A trip to the moon requires a rocket with multiple stages or otherwise the rocket equation will eat your lunch..." -- nullc, 2016-01-29

A collection of analysis about Bitcoin second-layers protocols' security and performance with regards to their base layer interactions. The purpose of this documentation is to spread knowledge of L2's onchain security and perfomance open problems among the Bitcoin protocol dev community and hopefully to assist in the design of solutions.

The first section outlines a list of known attacks against L2s, especially the class of attacks known as tx-relay jamming which exploits p2p and mempool acceptance rules.

The second section relates the performance of L2s in matters of fee-bumping, cooperative opening/closing dust selection, rebroadcasting, etc. It aims to illustrate how L2s are consuming base layers resources such as blockspace, bandwidth, utxo sets, mempool space, etc and trade-offs to think about when suggesting improvements.

The third section provides a survey of major L2 protocols architecture and onchain operations. Further, it outlines per-protocol the vulnerabilites and performance issues affecting them. It also directs towards known implementations and standards for each of them.

The last section submits to the dev community a list of discussions/questions about potential solutions to problems raised in the first sections.

Finally, a series of workshops are organized to foster discussion and development in these areas.

Feel free to contribute :)

Licensed under Apache 2.0