In a recent interview with The Defiant, David Schwartz, Chief Technology Officer at Ripple, shed light on the security mechanisms of the XRP Ledger and the theoretical attack strategies it could face. Schwartz explained that unlike Proof-of-Work systems like Bitcoin, the XRP Ledger relies on a Byzantine Fault Tolerance (BFT) consensus mechanism called the Ripple Protocol Consensus Algorithm (RCPΑ) for security.
How The XRP Ledger Could Theoretically Be Attacked
Here’s how Schwartz describes it: “The only problem you can’t fix [with every node enforcing every rule] is the double spend problem […] the only way that you could sort of attack the XRP Ledger was to stop the global ordering from working and that would just cause the whole the whole network to halt.”
This “global ordering” refers to validators agreeing on a specific sequence for transactions, preventing them from being spent twice. Disrupting this order would indeed halt the network. Schwartz acknowledges the possibility of an attack, but downplays its feasibility.
“Really the only plausible attack on the XRP Ledger is just to stop it,” he said. However, he reasons that such an attack would be difficult to monetize and would quickly lose effectiveness “as soon as somebody caused the XRP Ledger to halt people would just stop listening to them.”
Schwartz also acknowledges a potential motive for a disruption attack. “The one reason I imagine people would want to attack the system is if they were short XRP […] you’d imagine XRP might fall in value if the network stops.” However, he argues that the knowledge of this potential attack would make it difficult to borrow XRP for shorting to a risky degree.
Launching such an attack would require accumulating trust through proof-of-association within the network. Schwartz argues that validators chosen for their trustworthiness would be unlikely to collude in an attack.
“When you choose the participants that you’re willing to work with to come to a consensus your sole criteria is they’re not going to collude to break the network […] if you’re specifically choosing people by their unlikelihood to collude to break the network and nevertheless they still collude to break the network, you’re like the worst at choosing possible.”
Schwartz compares this attacker difficulty to Proof-of-Work systems: “Whoever has the most [power] can launch that exact same type of attack […] being forced to trust the party that has the most money is somehow a better model.”
Schwartz downplays the practicality of the attack, highlighting the difficulty and limited window for disruption. “In practice it’s an extremely difficult attack to launch and you would only be able to halt the network once for a fairly short period of time,” he said. He compares it to the double-spend attack in Bitcoin, something users should be aware of but not overly worried about: “I would say this is kind of in the same category.”
The interview concluded with Schwartz mentioning the current network size. “I think last I checked, there were about 600 nodes of which a little over a hundred of them were actually participating in the validation process,” he stated. This structure is similar to the distinction between full nodes and mining nodes in the Bitcoin network.
The XRP Ledger’s design prioritizes security through its consensus mechanism. While a disruption attack is theoretically possible, Schwartz emphasizes the difficulty and limited impact of such an attempt. However, as with any system, security remains an ongoing conversation, and Ripple’s approach has its own considerations, such as the reliance on trusted validators.
At press time, XRP traded at $0.52.
