
SW3
GIGABIT/FAST ETHERNET SWITCH TYPE SW3 (DIN)
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USER GUIDE - M0SW3D1905Iv04 - V04 May 2019
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Forward All.
Indicates the status of the special group address for the corresponding
interface. Valid values are
Normal
,
Fixed
and
Forbidden
. The
Normal
option is the
default option. It indicates that the spread or not of the multicast traffic is subjected to
there being a client equipment that requested the register for the group address. The
Fixed
option means that the interface will propagate all multicast traffic, and GMRP
messages concerning the group address is ignored. The
Forbidden
option assumes
that requests won´t be accepted by the client devices for the group address, and that
only the multicast traffic registered in the interface will be treated.
FIGURE 39
GMRP
configuration page of
Multicast
menu
5.13.3
IGMP
The IGMP Snooping is an optimization to be used in level 2 devices, such as the SW3. The
IGMP protocol is level 3; therefore, the IGMP Snooping operation performed by the switch
is conditioned by the presence of a Multicast router in the network.
The SW3 includes a special feature if there is NO multicast router in the network, and if the
IGMP Snooping operation has to be active. Said feature implies that the switch itself
emulates the presence of a multicast router, by periodically consulting the clients about
belonging to the different multicast diffusion groups.