Anil
Is the encoder connected to the same switch as the cameras ?
If not you may have an issue with IGMP snooping. You have 2 options -
1) on the 6500 switch turn on the IGMP snooping querier function for the camera vlan
or
2) turn off IGMP snooping on your switches as it is on by default.
Actually the 3rd option is to enable PIM under the camera vlan interface but i'm assuming you do not want to enable multicast routing.
Jon
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