Hi,
I wanted to know if the entire network map is made available to each and every node OR the node has information only about its local connectivity to its neighbors and max the neighbors immediate connectivity.
I'm not entirely sure about your question but I'll do my best to answer it. Once you enable the vis server the node will activate a flag in his originator messages indicating that you can send vis information. All nodes receiving this OGM will send their vis client data to this node. If you have several vis servers (due to out fo range problems) the nodes will send their information to the nearest vis server whereas the vis server themselves will sync with each other.
Hope it helps clarifying the situation, Marek