Hybrid Jamming Mitigation: Results and Updates

In the exploration of sink attacks within a blockchain network, the focus is on the flow of Hashed Time-Locked Contracts (HTLCs) between nodes, specifically from a peer's target to the largest node, illustrating the vulnerability through a graphical representation. This visualization simplifies the understanding of how such attacks are structured and how they propagate across the network, adhering to the principle of Occam’s razor by suggesting that connecting neighbor's peers might be unnecessary for analyzing the core mechanics of the attack.

The method for calculating a node's reputation delta is detailed, highlighting the incorporation of various factors such as outgoing reputation, in-flight risk, HTLC risk, and incoming revenue. The formula underscores an observable limitation related to the equal treatment of in_flight_risk and the sum of outstanding_risk for each non-endorsed HTLC, considering the disparities that can arise due to different height_added for a HTLC forward in the outgoing channel. This inconsistency points towards the complexity in accurately modeling the reputational impact of these variables, given the variance in block propagation times which could advantageously be exploited in a jamming attack.

Further analysis raises the question of whether HTLC risk should conversely be accounted for as a positive contribution to a node’s outgoing reputation since unsettled HTLCs may potentially increase the incoming_revenue of the outgoing channel. This perspective introduces a nuanced consideration of the role that yet-to-be-settled HTLCs play in the economic balance of the network, suggesting that their presence might not unequivocally translate to a reputational detriment.

The strategic considerations for nodes forwarding HTLCs highlight the necessity for nodes, particularly node T in the described scenario, to evaluate the implications of forwarding HTLCs on their reputational standing and potential traffic. This includes assessing the traffic from hypothetical alternative paths that might coexist with or compete against the direct path from node A to T, thereby influencing the decision-making process regarding which HTLCs to forward. This deliberation suggests a dynamic approach to managing congestion based on a comprehensive assessment of all incoming channels, indicating the complex interplay between network traffic, reputational concerns, and the economic incentives driving node behavior.