By CCN: Stellar, the Ripple fork founded by Jed McCaleb after disagreements with decisions at Ripple, went down for about two hours yesterday. Tim Swanson alerted Twitter to the issue, and a Stellar representative confirmed its occurrence.
Experts Notice, Story Goes Viral, Stellar Goes On Defense
Breaking: yesterday the Stellar network went down for about 2 hours… only those who run validators noticed it.
no new transactions were added for ~2 hours.
network stats:https://t.co/eSRYFPjDQi
— Tim Swanson (@ofnumbers) May 16, 2019
The incident raises questions about the level of decentralization in Stellar, which uses the same “validator” network design as Ripple. In this design, a few servers validate the transactions of the network at large, and if these servers experience problems, the system can quickly become unusable.
Stellar Improving Decentralization
Stellar’s chief scientist confirmed last month that decentralization is a concern for Stellar. His blog post from April is a response to a separate report by researchers who conclude that Stellar is too centralized to be considered “secure.” The researchers wrote:
“As can be seen from many articles and papers, some network attacks, such as DDoS, can occur in the blockchain networks. In this paper, we are saying that if two centralized nodes can not receive or send any message because of DDoS, then all nodes in Stellar network wull [sic] be blocked and can not move to the next step in the consensus process.”
Jed McCaleb says that Stellar Development Foundation nodes aren’t purely to blame for the outage and that the project has been working on getting people to rely less on these nodes.
“Over the last months we have worked to get people to *not* depend on the SDF nodes. As of maybe a month or so ago the SDF nodes could safely go down and the network would continue. But this also means that the network can halt even if the SDF nodes are still running. Unfortunately this is what happened. Enough other nodes stopped for various reasons that the network halted. The SDF nodes and in fact the majority of validators in the network were still up. They just couldn’t close ledgers safely because they weren’t hearing from enough nodes in their quorums so the network halted until it could be restored to a good state.”
Luckily It Wasn’t Bitcoin or EOS
The effect would be amplified on more active networks, but as Swanson pointed out, activity on Stellar is relatively small by comparison to other networks.
what basically happened was that a critical mass of nodes went down causing a cascading failure and so the entire network went down but because it isn’t frequently used, few noticed.
this scenario was discussed in a new paper from @yongdaek et al. https://t.co/MWhoywnMg3#XLM
— Tim Swanson (@ofnumbers) May 16, 2019
Therefore, few people noticed the network was down. It’s the equivalent of a majority of miners going offline in Bitcoin, and the remaining miners effectively being unable to find blocks to support the network.
Stellar recently announced a partnership with IBM which boosted sentiments toward the cryptocurrency. Ripple and Stellar work in an increasingly fractured marketplace, where some banks have chosen to create blockchain solutions as opposed to utilizing these “industrial” products.
