Web Management Guide-R07

Table Of Contents
Chapter 1
| Introduction
Description of Software Features
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members from being segmented from the rest of the group (as sometimes
occurs with IEEE 802.1D STP).
Virtual LANs The switch supports up to 4094 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. 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, except
where a connection is explicitly defined via the switch's routing service.
Use protocol VLANs to restrict traffic to specified interfaces based on protocol
type.
IEEE 802.1Q Tunneling
(QinQ)
This feature is designed for service providers carrying traffic for multiple customers
across their networks. QinQ tunneling is used to maintain customer-specific VLAN
and Layer 2 protocol configurations even when different customers use the same
internal VLAN IDs. This is accomplished by inserting Service Provider VLAN
(SPVLAN) tags into the customers frames when they enter the service provider’s
network, and then stripping the tags when the frames leave the network.
Traffic Prioritization This switch prioritizes each packet based on the required level of service, using
eight priority queues with strict priority, Weighted Round Robin (WRR) scheduling,
or a combination of strict and weighted 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 priority
bits in the IP frames Type of Service (ToS) octet using DSCP, or IP Precedence. 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.
Quality of Service Differentiated Services (DiffServ) provides policy-based management mechanisms
used for prioritizing network resources to meet the requirements of specific traffic
types on a per-hop basis. Each packet is classified upon entry into the network