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Forwarding Traffic with Unknown VLAN Tags
Up to 2048 VLANs are supported by the IEEE 802.1Q protocol, but
this switch only supports 16 VLANs. Therefore, if this switch is
attached to any device that forwards frames with unknown VLAN
tags, or to endstations which issue VLAN registration requests for
unknown VLANs, this traffic will be dropped.
Class-of-Service (CoS) Support
The TigerSwitch 1000 provides two transmit queues on each port,
with a weighted round-robin scheme. This function can be used to
provide independent priorities for various types of data such as
real-time video or voice, and best-effort data.
Priority assignment to a packet in the TigerSwitch 1000 is
accomplished through explicit assignment by end stations which
have applications that require a higher priority than best-effort.
This switch utilizes the IEEE 802.1p and 802.1Q tag structure to
decide priority assignments for the received packets.
IGMP Snooping and IP Multicast Filtering
The Internet Group Management Protocol (IGMP) runs between
hosts and their immediately neighboring multicast router/switch.
The protocol's mechanisms allow a host to inform its local router
that it wants to receive transmissions addressed to a specific
multicast group.
A router, or multicast-enabled switch, can periodically ask their
hosts is they want to receive multicast traffic. If there is more than
one router/switch on the LAN performing IP multicasting, one of
these devices is elected "querier" and assumes the responsibility of
querying the LAN for group members.
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