Design and investigation of scalable multicast recursive protocols for wired and wireless ad hoc networks

Table 4.2 Messages used in SReM

4.3 Membership Management

4.3.1 Dynamic Branching node-based Tree (DBT)

In SReM, the interaction between branching nodes due to multicast group member joins
and/or leaves, leads the setup of the multicast tree dynamically and gradually, rather than in
advance. Therefore, the multicast tree is referred to as a dynamic branching node-based tree
(DBT). The two types of branching node messages used to set up the DBT are enquiring
BNM (eBNM) and replying BNM (rBNM). These two messages carry information like
previous branching node address, next branching node address and new Local Multicast-
enabled Router (LMR).

The key point in setting up the DBT is that each Intermediate Multicast Router (IMR) is
aware whether it is a BNR or not. So, IMRs have three functions: -

■ Know its state as a BNR or not.

59

<<   <   70   71   72   73   74   75   76   >   >>