Digisol DG-FS4526E, Management Manual

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C
HAPTER
1 | Introduction
Description of Software Features
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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.
Multiple Spanning Tree Protocol (MSTP, IEEE 802.1s) – This protocol is
a direct extension of RSTP. It can provide an independent spanning tree
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 (as sometimes occurs with IEEE 802.1D STP).
C
ONNECTIVITY
F
AULT
M
ANAGEMENT
The switch provides connectivity fault monitoring for end-to-end
connections within a designated service area by using continuity check
messages which can detect faults in maintenance points, fault verification
through loop back messages, and fault isolation with link trace messages.
V
IRTUAL
LAN
S
The switch supports up to 4093 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,
except where a connection is explicitly defined via the 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 allowing you to limit the total number of VLANs that need to
be configured.
Use protocol VLANs to restrict traffic to specified interfaces based on
protocol type.
IEEE 802.1Q
T
UNNELING
(Q
IN
Q)
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 customer’s