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1.1.29.
MAC Multicast Support
Multicast service is a limited broadcast service that allows one-to-many and many-to-many connections. In
Layer 2 multicast services, a single frame addressed to a specific multicast address is received, and copies of
the frame to be transmitted on each relevant port are created.
1.1.30.
IGMP Snooping
Internet Group Management Protocol (IGMP) Snooping is a feature that allows a switch to forward
multicast traffic intelligently on the switch. Multicast IP traffic is traffic that is destined to a host group.
Host groups are identified by class D IP addresses, which range from 224.0.0.0 to 239.255.255.255. Based
on the IGMP query and report messages, the switch forwards traffic only to the ports that request the
multicast traffic. This prevents the switch from broadcasting the traffic to all ports and possibly affecting
network performance.
1.1.31.
Source Specific Multicasting (SSM)
This mechanism provides the ability for a host to report interest in receiving a particular multicast stream
only from among a set of specific source addresses, or its interest in receiving a multicast stream from any
source other than a set of specific source addresses.
1.1.32.
Control Packet Flooding
This feature enhances the MGMD Snooping functionality to flood multicast packets with DIP=224.0.0.x to
ALL members of the incoming VLAN irrespective of the configured filtering behavior. This enhancement
depends on the ability of the underlying switching silicon to flood packets with DIP=224.0.0.x irrespective of
the entries in the L2 Multicast Forwarding Tables. In platforms that do not have the said hardware
capability, 2 ACLs (one for IPv4 and another for IPv6) would be consumed in the switching silicon to
accomplish the flooding using software.
1.1.33.
Flooding to mRouter Ports
This feature enhances the MGMD Snooping functionality to flood unregistered multicast streams to ALL
mRouter ports in the VLAN irrespective of the configured filtering behavior. This enhancement depends on
the ability of the underlying switching silicon to flood packets to specific ports in the incoming VLAN when
there are no entries in the L2 Multicast Forwarding Tables for the specific stream. In platforms that do not
have the this hardware capability, incoming multicast streams will always be flooded in the ingress VLAN
when there is a L2MC-MISS in the switching silicon.
1.1.34.
IGMP Snooping Querier
When Protocol Independent Multicast (PIM) and IGMP are enabled in a network with IP multicast routing,
the IP multicast router acts as the IGMP querier. However, if it is desirable to keep the multicast network
Layer 2 switched only, the IGMP Snooping Querier can perform the query functions of a Layer 3 multicast
router.
Summary of Contents for QuantaMesh QNOS5
Page 1: ...QuantaMesh Ethernet Switch Configuration Guide QNOS5 NOS Platform ...
Page 209: ...209 Table 7 8 IPv6 Neighbor Discovery Settings ...
Page 226: ...226 Table 8 2 L3 Multicast Defaults ...
Page 254: ...254 Appendix A Term and Acronyms Table 9 5 Terms and Acronyms ...