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Chapter 4: Web configuration
NS3562-8P-2S User Manual 99
Port -6 & 7= Tagged,
Port-1~3 = Excluded.
Spanning Tree Protocol (STP)
Theory
STP can be used to detect and disable network loops, and to provide backup links
between switches, bridges, or routers. This allows the switch to interact with other
bridging devices in the network to ensure that only one route exists between any two
stations on the network, and provides backup links that automatically take over when a
primary link goes down. The spanning tree algorithms supported by this switch include
these versions:
• STP
–
Spanning Tree Protocol (IEEE 802.1D)
• RSTP
–
Rapid Spanning Tree Protocol (IEEE 802.1w)
• MSTP
–
Multiple Spanning Tree Protocol (IEEE 802.1s)
The IEEE 802.1D Spanning Tree Protocol and IEEE 802.1w Rapid Spanning Tree
Protocol allow for the blocking of links between switches that form loops within the
network. When multiple links between switches are detected, a primary link is
established. Duplicated links are blocked from use and become standby links. The
protocol allows for the duplicate links to be used in the event of a failure of the primary
link. Once the STP is configured and enabled, primary links are established and
duplicated links are blocked automatically. The reactivation of the blocked links (at the
time of a primary link failure) is also accomplished automatically without operator
intervention.
This automatic network reconfiguration provides maximum uptime to network users.
However, the concepts of the spanning tree algorithm and protocol are a complicated
and complex subject and must be fully researched and understood. It is possible to
cause serious degradation of the performance of the network if the spanning tree is
incorrectly configured. Please read the following before making any changes from the
default values.
The switch STP performs the following functions: