Recently, a miner in Discord about relay:
“It’s dependent on location and neighbor node right? I’m confuse in this country only my 6 node online, why I’m get high relay?”
So here is a simple answer with more reference material for a deeper dive.
In NKN p2p network, a node’s neighbors are not physical neighbors in terms of geographic location. All nodes in the entire NKN network are mapped to a giant virtual ring (DHT) based on their NKN ID, and neighborhood is defined in the virtual ring.
Therefore at any particular time, some nodes might be more lucky to have lots of virtual neighbors that ask them to relay lots of message, while others might get less. It also depends on the speed and throughput of this particular node to his virtual neighbors.
But luck can be changed over time, as new nodes join the network, and old nodes leave the network. These events will change the topology of the virtual ring, then previously unlucky nodes might become lucky ones.
The one ring that rules them all! 
For a beginner’s primer on NKN technology:
For more details, here is a more academic investigation:
Or watch Yilun’s presentation:
