In the second scenario a DBT change has happened because of roaming of mobile node x.
This scenario can happen in one of the following cases:
J Case 1 : the mobile receiver x is the last receiver attached to oLMR and it is not
the first mobile receiver attached to the nLMR.
J Case 2: the mobile receiver x is not the last receiver attached to oLMR but it is
the first mobile receiver attached to the nLMR.
J Case 3: the mobile receiver x is the last receiver attached to oLMR and it is the
first mobile receiver attached to the nLMR.
All of these cases will cause a DBT update, including BNRs update and MFTs update at
BNRs.
Figure 5.1 Roaming process in (case 1)
|
Nodes |
MFTs | |
|
Before x join |
Afterx join | |
|
S (Source) |
MTI | IP_N1 |
unchanged |
|
N1 |
MTI | IP_N2 &IP_M4 |
unchanged |
|
N2 |
MTI | IP_N3 , IP_M3, IP_M5 |
MTI | IP_M1 , IP_M5, IP_M5 |
|
N3 |
MTI | IP_M1 & IP_M2 |
non BNR |
Roaming messages (Rm out, Rm in)
Moving direction
Starting with case 1, Figure 5.1 shows this case; when roaming is transport to the
receivers, it will send an Rm_out message towards its oLMR (M2). Upon receiving this
message and checking its MDT, x’s oLMR (M2) will be aware that it will no longer be a
multicast branch. As a result, N3 will delete its M2 entry in its MFT for the multicast
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