Bitcoin node P2P traffic analysis

The discussion highlights the significant challenge posed by long-term abusers on certain networks, who consume a substantial portion of the total non-initial block download (non-IBD) bandwidth. A notable suggestion to address this issue involves differentiating these networks in future reports due to their inability to benefit from advancements like Erlay, which optimizes transaction relay to reduce bandwidth usage. The proposed solution entails shipping a list of subnets designated to receive only blocks by default, aiming to mitigate unnecessary bandwidth consumption.

The concept of listening nodes is clarified with a distinction made between archive nodes (or listening archive nodes) and pruned nodes. Archive nodes store the complete blockchain and accept connections, offering a potential area for bandwidth optimization. An observation is made that increasing the number of archive nodes that are set to listen, particularly given the low current percentage due to obstacles such as lack of NAT traversal, could significantly enhance network efficiency. Currently, a limited fraction of archive nodes accept connections, leading to disproportionate bandwidth usage among those that do.

A strategy to improve bandwidth usage involves adopting a more efficient encoding method for transferring blocks, mirroring techniques used in projects like the Blockstream satellite. Reference is made to BIP337, which proposes an alternative encoding mechanism that not only facilitates bandwidth reduction during transmission but also offers the possibility of disk space savings when applied to stored data. Additionally, assessing the distribution of block fetches within specific ranges—such as comparing requests for blocks closer to the chain's tip versus those further away—could provide insights into bandwidth wastage through incomplete synchronization processes, thereby identifying areas for further optimization.