MFT. The previous (upstream) BNR (N1) upon receiving the RqM1(10) will update its MFT
by removing the first BNR (N2) from its MFT and will check out that instead of (N2), N3
will be the new downstream BNR. Meanwhile (N1) will send RqM0(10) message towards
the source to complete the de-registration process. In leaving process, only in this case,
changes occurred to the DBT.
Figure 4.11 Leaving process in SReM (Case 3)
In the previous section and subsections a discussion of building and upgrading the DBT for a
multicast group session was performed. Next section will discuss about the delivering of data
in SReM.
Nodes |
MFTs | |
S (Source) |
MTI | IP_Nι |
unchanged |
N1 |
MTI | IP_N2 &IP_M4 |
MTI | IP_N3 &IP_M4 |
N2 |
MTI | IP_N3 & IP_M3 |
— |
N3 |
MTI | IP_M1 & IP_M2 |
unchanged |
Leave message
RqM
4.4.4 Tree maintenance
As discussed in the pervious sections, some cases in joining and leaving of receivers, changes
will occur in the DBT. The procedure of applying these changes to reconstruct the DBT and
continue the data flow is called tree maintenance.
In case 3 of joining a new receiver discussed before, changes will occur in the DBT. The
changes include a new branching node added to the DBT. The process of finding the new
BNR and updating the previous BNRs because of the new receiver joining is the scope of
discussion in this section.
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