Multicast: ip pim neighbor-filter : Stub Multicast Routing:

Stub Multicast Routing
Why ?
1) Save Upstream Router's Resources as the downstream Router doesnt participate in PIM anymore.....
2) Save RP's Resources as the downstream Router doesnt participate in PIM anymore.....
3) Security: Downstream Router now unaware of your RPs, Cannot advertise his groups to RP.
4) Security: Downstream Router cannot be the DR as well, since DR is elected via PIM. So you control who becomes the DR on a broadcast segment.

How ?

Receivers<--(f0/1)CE8 (f0/0)--(f0/0.82)PE2-->RP
PE2#sh run int f0/0.82
Building configuration...

Current configuration : 148 bytes
!
interface FastEthernet0/0.82
encapsulation dot1Q 82
ip address 10.82.1.2 255.255.255.0
ip pim neighbor-filter 3
ip pim sparse-dense-mode
end

PE2#

PE2#sh access-l 3
Standard IP access list 3
10 deny 10.82.1.1 (89 matches) --> This is the IP address of the CE8 interface f0/0
20 permit any
PE2#

By filtering off CE8, we no more have PIM neighborship with him on interface f0/0.82
Now CE8 cannot communicate with the Upstream Multicast Senders.

To enable this we have to conf following on CE8 where receivers are located ( int f0/1)
CE8 now communicates with PE2 via PIM Dense mode.
All traffic in CE8 is dense.

CE8#sh run int f0/1
Building configuration...

Current configuration : 349 bytes
!
interface FastEthernet0/1
ip igmp helper-address 10.82.1.2
CE8#