Multicast Support; Igmp Setting - Dell PowerConnect 5224 System User's Manual

CLI Commands
The following table summarizes the equivalent CLI commands for items in the SNMP/Traps page.
Command
snmp-server host host-addr community-string
snmp-server enable traps [authentication | link-up-
down]
Example
Console(config)#snmp-server host 10.1.19.23
Console(config)#snmp-server enable traps link-up-down
Console(config)#

Multicast Support

Multicasting is used to support real-time programs such as video conferencing or streaming audio. A multicast server does not have to establish a separate
connection with each client. Instead, it broadcasts its service to the network and to any hosts that are supposed to receive the multicast register with their
local multicast routers/switches. This approach reduces the network overhead required by a multicast server. However, each time the broadcast traffic passes
through a multicast router/switch, the traffic must be carefully queried to ensure that only hosts that subscribe to the service receive the broadcast.
The switch uses the Internet Group Management Protocol (IGMP) to determine if any attached hosts are supposed to receive a specific IP multicast service.
IGMP runs between hosts and their adjacent multicast routers/switches. IGMP is a multicast host registration protocol that allows any host to inform its local
router that the host is supposed to receive transmissions addressed to a specific multicast group.
IGMP requires one device to act as the querier on each LAN subnetwork. The querier is the IGMP-enabled device that periodically sends query messages to all
hosts asking them if they want to receive multicast traffic. Hosts respond with report messages, indicating to multicast groups that they wish to join or to
which group they already belong. The querier then propagates the service requests on to any adjacent multicast switch/router to ensure that it continues to
receive the multicast services.
IGMP-enabled devices prune multicast traffic on the network by passively snooping on IGMP report messages passing through their ports. The devices monitor
host report messages, pick out the multicast group registration information, and then configure filters accordingly so that multicast traffic for particular groups
is not forwarded on to ports that do not require it. This capability significantly reduces the multicast traffic on the network.
The Multicast Support page contains links to the following pages:

IGMP Setting

l
IGMP Member Port Table
l
Multicast Router Port Settings
l
IGMP Setting
With IGMP Snooping, you can configure the switch to forward multicast traffic intelligently. Based on the IGMP query and report messages, the switch forwards
traffic only to the ports that request multicast traffic. This querying prevents the switch from broadcasting the traffic to all ports and possibly disrupting
network performance.
NOTE: IGMP requires a router that learns about the presence of multicast groups on its subnets and keeps track of group membership.
On the IGMP Setting page, the following options are available:
IGMP Status — Enables IGMP. When IGMP is enabled, the switch monitors network traffic to determine which hosts are supposed to receive multicast
l
traffic.
Usage
Specifies the recipient of a SNMP notification
operation
Enables the device to send SNMP traps