Enterasys VH-2402-L3 Management Manual page 126

The VH-2402-L3 STP allows two levels of spanning trees to
be configured. The first level constructs a spanning tree on
the links between switches. This is referred to as the Switch
or Global level. The second level is on a port group basis.
Groups of ports are configured as being members of a
spanning tree and the algorithm and protocol are applied to
the group of ports. This is referred to as the Port or VLAN
level.
On the switch level, STP calculates the Bridge Identifier for
each switch and then sets the Root Bridge and the
Designated Bridges.
On the port level, STP sets the Root Port and the
Designated Ports.
The following are the user-configurable STP parameters for
the switch level:
Parameter
Bridge Identifier
(Not user-
configurable
except by setting
priority below)
Priority
Hello Time
Maximum Age
Timer
118 VH-2402-L3 Management Guide
Description
A combination of the User-set
priority and the switch's MAC
address. The Bridge Identifier
consists of two parts: a 16-bit
priority and a 48-bit Ethernet
MAC address
A relative priority for each
switch – lower numbers give a
higher priority and a greater
chance of a given switch being
elected as the root bridge
The length of time between
broadcasts of the hello
message by the switch
Measures the age of a
received BPDU for a port and
ensures that the BPDU is
discarded when its age
exceeds the value of the
maximum age timer.
Default
Value
32768 + MAC
32768
2 seconds
20 seconds
9033691-01