Why should SPV nodes operate on the P2P network?


I understand there are advantages for the SPV client to acquire header-chain and subsequent inclusion proofs over the p2p network:

  • Peer discovery
  • P2P node interface is public
  • Reuse of P2P messaging protocol

But this must come at a cost for full-validating nodes:

  • Reduced channel bandwidth with full-nodes
  • Therefore, increased tx/block propagation times

Why are SPV nodes/clients not serviced over separate server-client interface rather than the P2P protocol? What are the justifications for this?

Thanks in advance.

James C.

Posted 2019-01-20T12:50:06.253

Reputation: 2 323

How would using a different protocol between lightweight nodes and full nodes not equally reduce channel bandwidth for the latter? – Pieter Wuille – 2019-01-20T23:06:45.420

P2P channels are generally long-lived. SPV nodes represent additional hop in data propagation without additional decentralisation (validation). I suppose a full-node could selectively drop SPV peers, but a server-client interface seems more efficient vs. P2P for those nodes which wish to act as public servers for SPV clients. – James C. – 2019-01-21T08:01:16.813

No answers