Tripp Lite NGI-S08C2POE8, Руководство пользователя

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Instance
The instance ID.
Control VLAN The control VLAN of the instance.
Data VLAN The data VLANs of the instance.
4.5.2. STP/RSTP
(R)STP detects and breaks network loops and provides backup links between switches, bridges
or routers. It allows a Switch to interact with other (R)STP compliant switches in your network
to ensure that only one path exists between any two stations on the network.
The Switch supports Spanning Tree Protocol (STP) and Rapid Spanning Tree Protocol (RSTP)
as defined in the following standards.

IEEE 802.1D Spanning Tree Protocol

IEEE 802.1w Rapid Spanning Tree Protocol
The Switch uses IEEE 802.1w RSTP (Rapid Spanning Tree Protocol) that allows faster
convergence of the spanning tree than STP (while also being backwards compatible with
STP-only aware bridges). In RSTP, topology change information is directly propagated
throughout the network from the device that generates the topology change. In STP, a longer
delay is required as the device that causes a topology change first notifies the root bridge and
then the root bridge notifies the network. Both RSTP and STP flush unwanted learned
addresses from the filtering database.
In STP, the port states are Blocking, Listening, Learning, Forwarding.
In RSTP, the port states are Discarding, Learning, and Forwarding.
Note : In this document, “STP” refers to both STP and RSTP.
STP Terminology

The root bridge is the base of the spanning tree.

Path cost is the cost of transmitting a frame onto a LAN through that port. The
recommended cost is assigned according to the speed of the link to which a port is
attached. The slower the media, the higher the cost.

On each bridge, the bridge communicates with the root through the root port. The
root port is the port on this Switch with the lowest path cost to the root (the root path
cost). If there is no root port, then this Switch has been accepted as the root bridge of
the spanning tree network.