Broadcast Filtering - NETGEAR ProSAFE Plus Series Reviewer's Manual

• from TG port 1 and 3, send packets to each other for 2 seconds.
• from TG port 2 and 4, send packets to each other for 2 seconds.
• The purpose of above 2 steps is to make sure Switch A has learned TG port 1 and 2 MAC address and Switch B has learned TG
port 3 and 4 MAC address.
• from TG port 1 and port 2, send 1,000,000 packets to Switch A simultaneously.
EXPECTED RESULT: The received packet ratio for TG port 3 and port 4 should be 4:1 respectively.

Broadcast Filtering

The Broadcast filtering enables each port to drop broadcast packets (destination MAC is ff:ff:ff:ff:ff:ff) after a continuous
received broadcast packets counter count of 64. The counter is reset to 0 every 800ms.
Test Network Topology
Same topology as Port Mirroring test
• Connect TG port 1 to Switch A port 1.
• Connect TG port 2 to Switch A port 2
• Connect TG port 3 to Switch A port 3.
• Enable Broadcast filtering.
• from TG port 1, send 50,000 broadcast packets to Switch A.
EXPECTED RESULT: only several hundreds of packets are received on TG port 2 and port 3.
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.
To enable or disable IGMP snooping:
• S elect Disable or Enable for IGMP Snooping Status and click Apply.
or
• Y ou can also change the VLAN for which the IGMP Snooping to be enabled by entering a valid VLAN ID for the field "VLAN ID
Enabled for IGMP Snooping"; and clicking Apply.
This field is greyed out if VlAN is not enabled.
Validate IGMPv3 IP header:
Some of the Network devices may not conform to the IGMPv3 standard. When 'Validate IGMPv3 IP header' option is enabled, IGMP
messages are required to have TTl = 1, ToS Byte = 0xC0 (Internetwork Control), and router alert IP option (9404) set; otherwise,
the packets will be ignored.
Block unknown MultiCast Address:
When enabled, multicast packets are forwarded only to the ports that are in the Multicast group learnt from IGMP snooping. All
unknown multicast packets are dropped.
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