N-Tron 708M12 user manual TX8

Example 6 – Basic understanding of VLANs with Multicast Filt ering

Top of Form

Bottom of Form

Receiving	Tagged VID	Destination	Transmitting	Notes
Port #	in packet	Address	Port #s
TX1	Untagged	01:00:00:00:00:01	TX2	Goes to ports TX1-TX8, but TX1 can only
				send to TX2 (VLAN 4)
TX3	Untagged	01:00:00:00:00:02	TX6, TX8	Goes to ports TX2, TX6-TX8 (VLAN 3) but
				filter keeps it on ports TX6 and TX8 only
TX2	Untagged	01:00:00:00:00:01	TX1,TX3-TX8	Goes to ports TX1-TX8, but won’t go back
				out the port it came in on
TX2	Untagged	01:00:00:00:00:02	TX1,TX3-TX8	Goes to ports TX1,TX3-TX8
TX3	Untagged	01:00:00:00:00:01	TX2, TX4-TX8	Goes to ports TX2, TX4-TX8
TX6	Untagged	01:00:00:00:00:02	TX8	Goes to port TX8
TX3	Untagged	01:00:00:00:00:02	TX6, TX8	Goes to ports TX6 and TX8

Note: If there are multiple ports on different VLANs, the 708 will apply the static multicast address to the lowest VLAN-ID that is associated with one of the ports assigned to the static multicast address. If the lowest VLAN-ID contains all the ports assigned to the static multicast address (an umbrella VLAN), it will function for all those ports with no problems. This can be achieved with overlapping VLANs.

For further information and examples on overlapping vlans, see:

http://www.n-tron.com/pdf/OverlappingPortVLAN.pdf

Revision 071108 Page 99 of 102