Cisco 350 Series Administration Manual page 318

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• Packets passing through egress ports in the Multicast TV VLAN are untagged.
• The port's Frame Type parameter is set to Admit All, allowing untagged packets (see
Interface Settings).
The Multicast TV VLAN configuration is defined per port. Customer ports are configured to
be member of Multicast TV VLANs using the Port Multicast VLAN Membership page.
IGMP Snooping
Multicast TV VLAN relies on IGMP snooping, configured on the port:
• Subscribers use IGMP messages to join or leave a Multicast group.
• Device performs IGMP snooping and configures the access port according to its
Multicast membership on Multicast TV VLAN
The device decides for each IGMP packet that is received on an access port whether to
associate it with the access VLAN or with the Multicast TV VLAN according to the following
rules:
• If an IGMP message is received on an access port, with destination Multicast IP
address that is associated with the port's Multicast TV VLAN, then the software
associates the IGMP packet with the Multicast TV VLAN.
• Otherwise the IGMP message is associated to the access VLAN and the IGMP
message is only forwarded within that VLAN.
• The IGMP message is discarded if:
- The STP/RSTP state on the access port is discard.
- The MSTP state for the access VLAN is discard.
- The MSTP state for the Multicast TV VLAN is discard, and the IGMP message is
associated with this Multicast TV VLAN.
Differences Between Regular and Multicast TV VLANs
Table 1 Characteristics of Regular vs. Multicast TV VLANs
VLAN Membership
Regular VLAN
Source and all receiver ports
must be static members in the
same data VLAN.
Cisco 350, 350X and 550X Series Managed Switches, Firmware Release 2.4, ver 0.4
VLAN Management
Access Port Multicast TV VLAN
.
Multicast TV VLAN
Source and receiver ports cannot
be members in the same data
VLAN.