MultiCasting with applets ??

Hi
I would like to ask about how can i avoid the problem of using the multicast socket with the applet as i want to build an applet and i knew that multicasting is not applicable with applets
but also i wanna use multicast socket for the multicasting of data stream in conferencing project
so any suggestions related to this problem is appreciated
thanks alot in advance

That's not going to work; manually defining groups means static multicasting (ie not dynamic nor scalable). That sort of defeats the purpose of IGMP snooping.
The problem is Microsoft's default multicast range is incompatible with IGMP and switches.
When a multicast layer 3 address is mapped to layer 2 (for the switch multicast layer 2 address), only the last 23 bits of the IPv4 address come across. The other bits are lost as we need specify the ethernet OUID owned by iana. (01-00-5e).
So the default range by microsoft 239.0.0.1-239.0.0.255 maps out at the ethernet layer: 01-00-5e-00-00-01 to 01-00-5e-00-00-ff
The problem is, the 224.x.x.x mulicast control messages also map out like that, e.g. 224.0.0.1 maps to 01-00-5e-00-00-01.
So 224.0.0.1 and 239.0.0.1 map to the same ethernet (layer 2) mac address. Therefore the switch has no alternative but to broadcast as 224.0.0.1 = all nodes.
So try changing the default WDS address to something that wont get confused by the switch, e.g. 239.67.54.3 to 239.67.54.255.
Have tested this in a lab only but should fix the problem.
bye
Oh, bridge multicast forwarding is for when the traffic needs to be forwarded (ie to another switch or router). Filtering is only to be touched to block all multicast traffic - perhaps for permanent groups that need to be manually configured. You dont need to touch that.

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That's not going to work; manually defining groups means static multicasting (ie not dynamic nor scalable). That sort of defeats the purpose of IGMP snooping.
The problem is Microsoft's default multicast range is incompatible with IGMP and switches.
When a multicast layer 3 address is mapped to layer 2 (for the switch multicast layer 2 address), only the last 23 bits of the IPv4 address come across. The other bits are lost as we need specify the ethernet OUID owned by iana. (01-00-5e).
So the default range by microsoft 239.0.0.1-239.0.0.255 maps out at the ethernet layer: 01-00-5e-00-00-01 to 01-00-5e-00-00-ff
The problem is, the 224.x.x.x mulicast control messages also map out like that, e.g. 224.0.0.1 maps to 01-00-5e-00-00-01.
So 224.0.0.1 and 239.0.0.1 map to the same ethernet (layer 2) mac address. Therefore the switch has no alternative but to broadcast as 224.0.0.1 = all nodes.
So try changing the default WDS address to something that wont get confused by the switch, e.g. 239.67.54.3 to 239.67.54.255.
Have tested this in a lab only but should fix the problem.
bye
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Fritz

MultiCasting with applets ??

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