What increases a node's banscore? What factors contribute to the banscore? Does a node sending bad transactions increase its banscore? Does its using unnecessarily too much bandwidth also increase its banscore?
- Sending invalid blocks.
- Sending duplicate version messages.
- Not sending first a version message (before other communication).
- Sending addr messages with more than 1000 addresses.
- Sending inv messages with more than 50000 elements.
- Sending header messages with more than 2000 elements.
- Sending too large bloom filters.
Regarding transactions, it seems that they also may increase the banscore:
// Punish peer that gave us an invalid orphan tx