A Persistent Structured Hierarchical Overlay Network to Counter Intentional Churn Attack

Algorithm 2

Peer join operation in proposed architecture.

Join ,

// node wants to join the overlay network and knows a node that is currently a member of overlay network.

  () If is a super node(top layer node), then

  () If host tree is responsible for , then

  () Go to step ().

  () Else

  ()  = Find_Tree()

   // joining node perform a tree lookup, which is routed in the top level overlay to the super node responsible for the key.

  () .Join_Tree()

  () else // if n₂ is not a super node

  () .Forward_Request(root) // node will forward the ’s join request to its root

  () if root node(host tree) is the super node responsible for the key, then

  () .Join_Tree()

  () else //if root node(host tree) is not responsible for the key

  () = Find_Tree()

  () .Join_Tree()

  () Return.

.Find_Tree

// node will find the super node responsible for node

  () = (, successor)

  () if

   // super node responsible for the key is found

  () return

  () else

   // forward the query to next node of the ring

  () .Find_Tree ()

.Forward_Request , Root

// Forward the join request from node to the root of the tree

  () If ( is not a root node), then

  () = parent()

  () .Forward_Request(, Root)

  () else

  () Root =

  () return