SMC Networks 8124PL2, Management Manual

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Introduction
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older IEEE 802.1D STP standard. It is intended as a complete replacement for STP,
but can still interoperate with switches running the older standard by automatically
reconfiguring ports to STP-compliant mode if they detect STP protocol messages
from attached devices.
Virtual LANs – The switch supports up to 255 VLANs. A Virtual LAN is a collection
of network nodes that share the same collision domain regardless of their physical
location or connection point in the network. The switch supports tagged VLANs
based on the IEEE 802.1Q standard. Members of VLAN groups can be dynamically
learned via GVRP, or ports can be manually assigned to a specific set of VLANs.
This allows the switch to restrict traffic to the VLAN groups to which a user has been
assigned. By segmenting your network into VLANs, you can:
• Eliminate broadcast storms which severely degrade performance in a flat network.
• Simplify network management for node changes/moves by remotely configuring
VLAN membership for any port, rather than having to manually change the
network connection.
• Provide data security by restricting all traffic to the originating VLAN.
• Use private VLANs to restrict traffic to pass only between data ports and the uplink
ports, thereby isolating adjacent ports within the same VLAN, and allowing you to
limit the total number of VLANs that need to be configured.
Traffic Prioritization – This switch prioritizes each packet based on the required
level of service, using eight priority queues with strict or Weighted Round Robin
Queuing. It uses IEEE 802.1p and 802.1Q tags to prioritize incoming traffic based on
input from the end-station application. These functions can be used to provide
independent priorities for delay-sensitive data and best-effort data.
This switch also supports several common methods of prioritizing layer 3/4 traffic to
meet application requirements. Traffic can be prioritized based on the DSCP field in
the IP frame. When these services are enabled, the priorities are mapped to a Class
of Service value by the switch, and the traffic then sent to the corresponding output
queue.
Multicast Filtering – Multicast filtering is a system where network devices forward
multicast traffic only to the ports that are registered with the multicast group. Without
mulicast filtering the data packet will be broadcast to all endstations within a LAN or
VLAN. The purpose is to keep the non-multicast group members from receiving
unsolicited packets and to prevent a possible reduction in network performance. The
switch uses IGMP Snooping and Query at Layer 2 and IGMP at Layer 3 to manage
multicast group registration.