Ericsson ECN330, User Manual

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Management Features Overview
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1553-KDU 137 365 Uen D 2006-06-16
network. This prevents the creation of network loops. However, if the
chosen path should fail for any reason, an alternate path will be
activated to maintain the connection.
• Rapid Spanning Tree Protocol (RSTP, IEEE 802.1w) – This protocol
reduces the convergence time for network topology changes to about 3
to 5 seconds, compared to 30 seconds or more for the IEEE 802.1D
STP standard. It is intended as a complete replacement for STP, but can
still interoperate with switches running the STP protocol, by
automatically reconfiguring ports to STP-compliant mode if they detect
STP protocol messages from attached devices.
• Multiple Spanning Tree Protocol (MSTP, IEEE 802.1s) – This protocol is
a direct extension of RSTP. It can provide independent spanning trees
for different VLANs. It simplifies network management, provides for
even faster convergence than RSTP by limiting the size of each region,
and prevents VLAN members from being segmented from the rest of the
group.
Virtual LANs – The ECN330-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 ECN330-switch
supports tagged VLANs based on the IEEE 802.1Q standard. Members of
VLAN groups can be dynamically learned through GVRP, or ports can be
manually assigned to a specific set of VLANs. This enables the ECN330-switch
to restrict traffic to the VLAN groups to which a user has been assigned.
Segmenting a network into VLANs can:
• Eliminate broadcast storms, which severely degrade performance in a
flat network.
• Simplify network management for node changes and moves by
remotely configuring VLAN membership for any port, rather than having
to manually change the network connection.
• Provide data security by restricting traffic to the originating VLAN,
except where a connection is explicitly defined by the ECN330-switch’s
routing service.
• 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 limiting the total number of VLANs that need to be configured.
• Use protocol VLANs to restrict traffic to specified interfaces based on
protocol type.