Duplex micropayment channels: criticisms of Lightning and implementation

Duplex micropayment channels: criticisms of Lightning and implementation

A paper from 2015 by Decker and Wattenhofer proposes an interesting design for a payment channel network, which differs from the Lightning network. The authors claim in the Related work section that Lightning:

• "requires exchanging keying material for each update in the channels, which results in either massive storage or computational requirements", and
• "cannot be decomposed into smaller units that can be analyzed in isolation, making the security analysis difficult and resulting in complex implementations".

I have two questions:

1. To what extent are those criticisms of Lightning valid as of November 2017?
2. Is there an implementation of Duplex micropayment channels or at least plans to create one?

http://ift.tt/2A8RLvj