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Fig. 4.
An example of the multicast tree for disseminating membership changes
The multicast tree disseminates messages all over the domain in collaboration,
workload are distributed to nodes. However, the workload in disseminating of each
node varies greatly, nodes closer to the tree root get more messages to cast [16],
sometimes exceeds nodes' bandwidth capacity. We propose another multicast tree for
disseminating called the binary-multicast tree for the structure is a binary tree.
A binary-multicast tree is also rooted at
JP
, among N nodes in its local table,
JP
selects its immediate successor and the
K
2(Kl g / 2
th
=
N
successor as its children
2
C
and
C
) in the tree, and asks them to cover the range (2, 2
K
(define as
−
1)
and
, respectively. Node
C
and
C
use a similar process to expand the tree
by adding their immediate successor and the
K
(2
+
1,
N
)
2
K
t
−
successor as children, and so
forth. The process stops when there is no node in the range. Figure 5 gives a brief
example of binary-multicast tree, Node 0 acts as the root of the tree and selects 1 and
4 as its children, each child of node 0 is responsible for a covering range, and they
also build their own tree to expand the binary-multicast tree.
1
Fig. 5.
Binary-multicast tree for disseminating membership changes
The binary-multicast tree disseminates messages with more reasonable and ba-
lanced bandwidth demands, nodes in a binary-multicast tree propagate update mes-
sages to only 2 other nodes at most (see figure 5), the tree is implicitly embedded in
the overlay, there is no message to construct the trees before use and no message to
tear down the trees after use. However, inaccurate routing tables are acceptable in
