BTC2019

In this course, we study the construction of the currently implemented payment channel mechanism. This is achieved by comparing the core idea of the construction with HTTP long polling.  We take a high level view on the bitcoin scripts that are needed to create a Revocable Sequence Maturity Contract. After this construction is explained we look at why getting rid of transaction malleability (which was achieved with the segwit upgrade) was crucial to be able to securely set up Lightning Network payment channels.

Understanding the basics of the cryptography we will also look at the Channel Protocol defined in BOLT 02 (Basics of Lightning Technologies or BOLT is the name of the protocol specification for the Lightning Network) which includes the communication and data flow between peers on the Lightning Network to open and close a payment channel.

We will also touch on problems and downsides (like asymmetric state or the difficulty to backup lightning nodes) with the current construction and proposals that could improve on them.

This course is appropriate for current and aspiring blockchain developers want to understand payment channels.

Prerequisite: a basic understanding of Bitcoin