Purging lazy neighbors - When does this happen and how?

Question

Node transaction propagation is a critical part of consensus and this feature can be seen as crucial so that the network operates as specified in the whitepaper.

In the Tangle whitepaper v1.4.3, a process is mentioned whereby 'lazy nodes' are purged.

What motivates the nodes to propagate transactions?

Let us also comment on the following question (cf. [4]): what motivates the nodes to propagate transactions?

Every node calculates some statistics, one of which is how many new transactions are received from a neighbor. If one particular node is “too lazy”, it will be dropped by its neighbors. Therefore, even if a node does not issue transactions, and hence has no direct incentive to share new transactions that approve its own transaction, it still has incentive to participate.

When is this done in the current network?

In order to keep their peer relationship balance within the network, how do they determine and go about dropping lazy neighbors and adding new replacement neighbors?

Answer 1

Current implementation of the IRI (1.5.3) :

• is collecting statistics (here and here is the code).
• don't implement anything regarding purge of lazy neighbors. (on the main net)

This task (i.e. purge of lazy neighbors) should be done either manually by the node operator, either through a third party script (like Nelson)