Allied Telesis AT-8600 Network Router User Manual


 
Page 23 | AlliedWare™ OS How To Note: IGMP
IGMP proxy > Explanation of IGMP proxy
Explanation of IGMP proxy
When there are no group members
The multicast server streams group 224.12.
1
3.
1
4 to switch
1
through port
1
. IGMP snooping
detects the stream, as you can see by using the command show igmpsnooping on switch
1
.
When a client joins a group
Client
1
(attached to switch 2, the Snooper) sends an IGMP Membership Report for the
group 224.
1
2.
1
3.
1
4. Switch 2 forwards that report message in an unmodified state out its All
Groups ports—in this case port 25.
Switch 3—the Proxy—receives the report on its downstream interface, vlan
1
00. Switch 3
then creates a new report with itself as the sender. It sends this report upstream to switch
1
Manager Switch 1> show igmpsnooping
IGMP Snooping
------------------------------------------------------------------------
Status ........................... Enabled
Disabled All-groups ports ........ None
Vlan Name (vlan id) ..... default (1)
Group List ..............
No group memberships.
Vlan Name (vlan id) ..... vlan200 (200)
Group List ..............
Group. 224.12.13.14 Entry timeout 122 secs
Ports None
------------------------------------------------------------------------
Manager Switch 2> show igmpsnooping
IGMP Snooping
------------------------------------------------------------------------
Status ........................... Enabled
Disabled All-groups ports ........ None
Vlan Name (vlan id) ..... default (1)
Fast Leave .............. Off
Group List ..............
No group memberships.
Vlan Name (vlan id) ..... vlan100 (100)
Fast Leave .............. Off
Group List ..............
Group. 224.12.13.14 Entry timeout 256 secs
Ports 2
All Groups Entry timeout 145 secs
Ports 25
------------------------------------------------------------------------