Suppression Of Unregistered Multicast Packets; Multicast Terms; Changing Global Ip Multicast Parameters; Multicast Groups - Dell PowerConnect B-FCXs Configuration Manual

Suppression of unregistered multicast packets

Be default, unregistered multicast packets are always forwarded in hardware but not copied to the
CPU. However, if Layer 2 multicast (IGMP or MLD) is enabled, then unregistered multicast packets
are forwarded in hardware and also copied to the CPU.

Multicast terms

The following are commonly used terms in discussing multicast-capable routers. These terms are
used throughout this chapter:
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Changing global IP multicast parameters

The following configurable parameters apply to PIM-DM, PIM-SM, and DVMRP:
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Changing dynamic memory allocation for IP

multicast groups

Layer 3 Switches support up to 1024 PIM groups and 1024 DVMRP groups by default. Memory for
the groups is allocated dynamically as needed. For each protocol, previous releases support a
maximum of 255 groups and 255 IGMP memberships.
PowerConnect B-Series FCX Configuration Guide
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Node: Refers to a router or Layer 3 Switch.
Root Node: The node that initiates the tree building process. It is also the router that sends the
multicast packets down the multicast delivery tree.
Upstream: Represents the direction from which a router receives multicast data packets. An
upstream router is a node that sends multicast packets.
Downstream: Represents the direction to which a router forwards multicast data packets. A
downstream router is a node that receives multicast packets from upstream transmissions.
Group Presence: Means that a multicast group has been learned from one of the directly
connected interfaces. Members of the multicast group are present on the router.
Intermediate nodes: Routers that are in the path between source routers and leaf routers.
Leaf nodes: Routers that do not have any downstream routers.
Multicast Tree: A unique tree is built for each source group (S,G) pair. A multicast tree is
comprised of a root node and one or more nodes that are leaf or intermediate nodes.
Maximum number of PIM groups – You can change the maximum number of groups of each
type for which the software will allocate memory. .PowerConnect B-Series FCX Layer 3
switches support up to 4000 PIM groups.
Maximum number of DVMRP groups – You can change the maximum number of groups for
which the software will allocate memory.
Internet Group Membership Protocol (IGMP) V1 and V2 parameters – You can change the
query interval, group membership time, and maximum response time.
Hardware forwarding of fragmented IP multicast packets – You can enable the Layer 3 Switch
to forward all fragments of fragmented IP multicast packets in hardware.
Changing global IP multicast parameters
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