Local Network - Igmp Snooping - NetVito RTV1835W-D90 User Manual

Local Network – IGMP Snooping
Traditionally, IP packets are transmitted in one of either two ways - Unicast
(1 sender to 1 recipient) or Broadcast (1 sender to everyone on the network).
Multicast delivers IP packets to just a group of hosts on the network.
Without IGMP snooping, multicast traffic is treated in the same manner as
broadcast traffic, that is, it is forwarded to all ports. With IGMP snooping,
multicast traffic of a group is only forwarded to ports that have members of
that group. IGMP snooping generates no additional network traffic, allowing
you to significantly reduce multicast traffic passing through your switch.
The figure below shows a simple network connected via the Wireless IAD.
There are four Ethernet clients and two wireless clients.
A
B
C
D
Etherent
Now suppose the video server is the multicast transmitter and host A and D
are multicast receivers. If we do not turn on the IGMP snooping function, the
IAD will forward the multicast traffic to all hosts on all interfaces and
consequently block and interrupt the traffic of wireless users, shown as the
following figure.
A
B
C
D
Etherent
ADSL Router
Wireless
E F
Multicast traffic
ADSL Router
Wireless
E F
Wireless IAD User Manual
Video Server
FANS FAN MULTI-
OK FAILURE FAN CAUTION
FAILURE When swapping this fan tray,
removal and replacement must
be done under two minutes or
system shutdown will be occur.
OA OB
PROCESSER ONLY
SUB
SLOT
0
SLOT SUB
1
PROCESSER ONLY
Video Server
FANS OK FAILURE FAN MULTI- FAN
FAILURE CAUTION
When swapping this fan tray,
removal and replacement must
be done under two minutes or
system shutdown will be occur.
OA OB
PROCESSER ONLY
SUB
SLOT
0
SUB
SLOT
1
PROCESSER ONLY
56