...Nodes can do fast sync with the friends to update this node map. MD4 signiture are used for fast sync.
Every working node serves a range. Every range could have 3 nodes working at the same time. If a new node has join a node map, it can find its job automatically.
The ranges would be able to cover the complete 0 ~ 0xffffffff area. That makes every hash result could find a responser node.