Laundry list of inter-peer wire protocol changes

Rusty Russell, a developer, discusses shachain and elkrem in an email conversation. He notes that shachain can be difficult to understand and proposes using the binary tree method instead. Russell provides pseudocode for generating values from the seed and deriving values from lesser indices and receiving new values. To derive previous values, one must find an element in the array from which the desired value can be derived. Russell also provides links to the design document and implementation code.