JetNet 4706/4706f Industrial Managed PoE Switch
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4.5.5 Command Lines for Network Redundancy
4.5.1 RSTP
RSTP stands for Rapid Spanning Tree Protocol. If a switch has more than one path to a
destination, it will lead to message loops that can generate broadcast storms and quickly bog
down a network. The spanning tree was created to combat the negative effects of message loops
in switched networks. A spanning tree uses a spanning tree algorithm (STA) to automatically
sense whether a switch has more than one way to communicate with a node. It will then select
the best path (primary), and block the other path(s). It will also keep track of the blocked path(s) in
case the primary path fails. Spanning Tree Protocol (STP) introduced a standard method to
accomplish this. It is specified in IEEE 802.1D-1998. Later, Rapid Spanning Tree Protocol (RSTP)
was adopted and represents the evolution of STP, providing for a much faster spanning tree
convergence after a topology change. This is specified in IEEE 802.1w. In 2004, 802.1w was
included into the 802.1D-2004 version. This switch supports both RSTP and STP (all switches
that supports RSTP are also backwards compatible with switches that support only STP).
This page allows you to enable/disable RSTP, and configure the global setting and port settings.
RSTP Mode:
You must first enable STP/RSTP mode before configuring any related parameters.
Parameter settings required for both STP and RSTP are the same. Note that 802.1d refers to
STP mode, while 802.1w refers to faster RSTP mode.
Bridge Configuration
Priority (0-61440):
RSTP uses bridge ID to determine the root bridge, the bridge with the highest
bridge ID becomes the root bridge. The bridge ID is composed of bridge priority and bridge MAC
address. So that the bridge with the highest priority becomes the highest bridge ID. If all of the
bridge IDs have the same priority, the bridge with the lowest MAC address will then become the
root bridge.
