D-Link DES-3226L, Manual

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DES-3226L Layer 2 Fast Ethernet Switch User’s Guide
Parameters that you can change are:
Parameter Description
Status This drop-down menu allows you to enable the Spanning Tree Protocol setting.
MAX. AGE (6-
40 SEC)
< 20 > – The Maximum Age can be from 6 to 40 seconds. At the end of the
Maximum Age, if a BPDU has still not been received from the Root Bridge, your
switch will start sending its own BPDU to all other switches for permission to
become the Root Bridge. If it turns out that your switch has the lowest Bridge
Identifier, it will become the Root Bridge.
Hello Time (1-10
sec) < 2 > – The Hello Time can be from 1 to 10 seconds. This is the interval between
two transmissions of BPDU packets sent by the Root Bridge to tell all other
switches that it is indeed the Root Bridge. If you set a Hello Time for your switch,
and it is not the Root Bridge, the set Hello Time will be used if and when your
switch becomes the Root Bridge.
Forward Delay
(4-30 sec) < 15 > – The Forward Delay can be from 4 to 30 seconds. This is the time any port
on the Switch spends in the listening state while moving from the blocking state
to the forwarding state.
PRIORITY (0-
61440)
< 32768 > – A Bridge Priority can be from 0 to 61,440. Zero is equal to the highest
Bridge Priority.
STP VERSION
Choose RSTP or STP compatible . Both versions use STP parameters in the
same way. RSTP is fully compatible with IEEE 802.1d STP and will function with
legacy equipment.
TX HOLD
COUNT (1-10)
This is the maximum number of Hello packets transmitted per interval. The count
can be specified from
1 to 10 . The default value is 3
FORWARDING
BPDU
This can be Enabled or Disabled . When it is enabled it allows the forwarding of
STP BPDU packets from other network devices when STP is disabled on the
switch. The default is enabled.
Note : Observe the following formulas when setting the above parameters:
Max. Age
≤
2 x (Forward Delay - 1 second)
Max. Age
≥
2 x (Hello Time + 1 second)
Note : The Spanning Tree Protocol (STP) operates on two levels: On the
switch level, the settings are globally implemented. On the port level, the
settings are implemented on a per user-defined Group basis.
Note : The factory default setting should cover the majority of installations.
However, it is advisable to keep the default settings as set at the factory,
unless it is absolutely necessary to change them.
Note : The Hello Time cannot be longer than the Max. Age. Otherwise, a
configuration error will occur.
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