For non-branching nodes, packets are forwarded just like normal unicast. Finally, when the
data packets arrive to the (LMRs), these packets will be delivered to the receivers by using
the standard multicast method.
4.5.2 Multicasting in confirmed mode
In SReM, the access control of multicast packets needs to be authenticated via the
registration process before being sent to the receivers. For convenience, in this thesis it’s
referred to this multicast as a Multicast in Confirmed mode (MCM). The first case of this
multicasting mode is shown in Figure 4.16 shows the data packet delivery in MCM in case a
new BNR created and explained as follows
New
Receiver
LMR
BNRn
(x)
IMRs
Sender
BNRn-1
IMRs IMRs
JoinM
RqM1
RqM1
Time (t)
RpM
»■
RpMi
RqM0
RqM0
RqM0 RqMo
Packet
Packet
----------( RpMo
Packet
RpM0
RpM0
RpMo
RqMo
-------->
RpMo
New
BNR
Figure 4.16 Data packet delivery in MCM in case a new BNR created
In this case a new BNR is created because of new member joining, discussed in Section 4.4.2
case 3, therefore in SReM, the multicast source is always in charge of the registration process
of members of a multicast group, but the delivery of multicast packets is fulfilled through
BNRs, exactly a ‘local’ BNR for a new member. Although the part of registration process
(initiated from BNRs) is always towards and through the multicast source, this process is fast
and expected to be finished almost at the time when BNRs are in place to deliver multicast
packets. This leads to efficient and less delay in the delivery of multicast packets. The other
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