New research: Lightning Network is becoming more and more centralized, the more nodes there are, the more centralized it becomes
The configuration of the Lightning Network (LN) is becoming more centralized and forming multiple centers. Here are the findings of an unreviewed research paper that was published on the preprinted website arXiv on February 7.
A group of scholars from Switzerland, France, Italy and Canada wrote this paper. Jian Hong-Lin and Kevin Primicerio performed the analysis, while others, including Blockstream Inc. researcher Christian Decker, participated in designing the study.
Core peripheral model
The team collected 18 months of Lightning Network information from January 18, 2018 to July 13, 2019. The researchers then analyzed this payment network based on Lightning Network nodes and wealth distribution.
They found that the network showed a high Gini coefficient both in terms of node concentration and wealth distribution. It is worth noting that the research results found that this value increases as more nodes are added.
It turns out that the Bitcoin (BTC) distribution on each node in the network is also extremely uneven. For example, when the Gini coefficient is 0.88, it is equivalent to 10% of the nodes holding 80% of BTC.
The purpose of this study is to understand which idealized model best describes this network. Although researchers consider the Undirected Binary Configuration Model (UBCM) to be a good choice, they have found that the network is more centralized than expected. The researchers concluded:
"This shows that BLN (Bitcoin Lightning Network) is becoming an increasingly centralized network and more and more compatible with the core peripheral structure."
An ideal network diagram based on 16-day and 34-day LN data. Blue indicates the central node. Source: Research paper .
This UBCM system does imply a certain degree of centralization, which will lead to the existence of multiple centers. Researchers believe that actual networks seem to rely too much on them, which could make them "targets for so-called split attacks."
16-day and 34-day actual LN plots. Orange and red indicate the central node. Source: Research paper .
The research paper follows the findings of BitMEX Research, which focused on a higher-than-expected number of "non-cooperative closures".
Lightning Network Progress
Lightning Network currently hosts more than 11,500 nodes with an average node capacity of $ 1,300 and an average channel capacity of just under $ 240. Back in September 2019, the network broke through 10,000 nodes.
Lightning Network also encountered some difficulties in the development process, and there are reports that users face temporary losses when adopting Lightning Network. In addition, a vulnerability was disclosed last September, and some reports have stated that the vulnerability was "exploited under natural conditions."
It is worth noting that the Lightning Network has made tremendous progress in adoption. Last December, the crypto exchange Bitfinex announced the introduction of support for Lightning Network, and users can make instant purchases through Bitrefill.