Page 23-3
Frame Flooding in Multicast
VLAN
s
Multicast traffic is flooded as follows in an environment that includes multicast
VLAN
s:
• If the destination address is a multicast address,
and
• if the destination multicast address is in the filtering database,
and
• if the destination multicast address is a specified multicast address for a multicast
VLAN
,
then
flood the traffic on all ports that have at least one multicast
VLAN
in common with the desti-
nation multicast address. This is illustrated below. If any of the conditions described above
are untrue, the traffic is flooded as it is for normal AutoTracker
VLANs
.
12345678
123456
Omni Switch/Router
Port 2
Client A
Client B
Client C
Client D
Server 1
Server 2
Group 3
Ports 1 – 6
Multicast
VLAN
10
Ports 3 and 4
Multicast address = CNN
Port 1
Port 3
Port 4
4
Multicast
VLAN
20
Ports 5 and 6
Multicast address = NBC
CNN
Port 6
Port 5
rt 5
CNN
NBC
NBC
Multicast
Address CNN
Multicast
Address NBC
When the Switch receives a frame with multicast destination address
CNN
from Server 1, the Switch locates the
CNN
multicast address in
the filtering database (or places the address into the filtering data-
base if it is not there already). The Switch then uses this address to
determine the multicast
VLAN
(s) – if any – out which to flood the
frame. In this example, the Switch determines that multicast
VLAN
10
should receive the frame, since multicast
VLAN
10 spec-
ifies multicast address
CNN
. The Switch
then checks through the port
records to determine if any ports
are assigned to multicast
VLAN
10. It finds ports 3 and 4 are so
assigned, and floods the frame
out those ports only.
For this Example, the Filtering Database is:
MAC
Address
Port
VLAN
Membership
Type
CNN
n/a
10
MVLAN
NBC
n/a
20
MVLAN
Server 1
1
1
BRIDGE
Server 2
2
1
BRIDGE
Client A
3
1
BRIDGE
Client B
4
1
BRIDGE
Client C
5
1
BRIDGE
Client D
6
1
BRIDGE
For this Example, the Port Records are:
Port
VLAN
Membership
MVLAN
Membership
1
1
none
2
1
none
3
1
10
4
1
10
5
1
20
6
1
20
The filtering database is a record of source
MAC
addresses, their ports of entry into the switch, and
their
VLAN
membership. Note that the ports of entry
for multicast addresses
CNN
and
NBC
are irrelevant
in the filtering database. This table is for informa-
tional purposes—it is not available in the UI.
The port records show the
VLAN
and multicast
VLAN
(MVLAN) membership of each port. This
table is for informational purposes only—it is
not available as a UI command.
Summary of Contents for Omni Switch/Router
Page 1: ...Part No 060166 10 Rev C March 2005 Omni Switch Router User Manual Release 4 5 www alcatel com ...
Page 4: ...page iv ...
Page 110: ...WAN Modules Page 3 40 ...
Page 156: ...UI Table Filtering Using Search and Filter Commands Page 4 46 ...
Page 164: ...Using ZMODEM Page 5 8 ...
Page 186: ...Displaying and Setting the Swap State Page 6 22 ...
Page 202: ...Creating a New File System Page 7 16 ...
Page 270: ...Displaying Secure Access Entries in the MPM Log Page 10 14 ...
Page 430: ...OmniChannel Page 15 16 ...
Page 496: ...Configuring Source Route to Transparent Bridging Page 17 48 ...
Page 542: ...Dissimilar LAN Switching Capabilities Page 18 46 ...
Page 646: ...Application Example DHCP Policies Page 20 30 ...
Page 660: ...GMAP Page 21 14 ...
Page 710: ...Viewing the Virtual Interface of Multicast VLANs Page 23 16 ...
Page 722: ...Application Example 5 Page 24 12 ...
Page 788: ...Viewing UDP Relay Statistics Page 26 24 ...
Page 872: ...The WAN Port Software Menu Page 28 46 ...
Page 960: ...Deleting a PPP Entity Page 30 22 ...
Page 978: ...Displaying Link Status Page 31 18 ...
Page 988: ...Displaying ISDN Configuration Entry Status Page 32 10 ...
Page 1024: ...Backup Services Commands Page 34 14 ...
Page 1062: ...Diagnostic Test Cable Schematics Page 36 24 ...
Page 1072: ...Configuring a Switch with an MPX Page A 10 ...
Page 1086: ...Page B 14 ...
Page 1100: ...Page I 14 Index ...