Stp System Configuration - Planet Networking & Communication SGS-5220 User Manual

The switch with the lowest Bridge ID (switch C) was elected the root bridge, and the ports were selected to give a high port cost
between switches B and C. The two (optional) Gigabit ports (default port cost = 20,000) on switch A are connected to one
(optional) Gigabit port on both switch B and C. The redundant link between switch B and C is deliberately chosen as a 100 Mbps
Fast Ethernet link (default port cost = 200,000). Gigabit ports could be used, but the port cost should be increased from the
default to ensure that the link between switch B and switch C is the blocked link.

4.7.2 STP System Configuration

This page allows you to configure STP system settings. The settings are used by all STP Bridge instances in the Switch or
Switch Stack. The Managed Switch support the following Spanning Tree protocols:
‧ Compatiable -- Spanning Tree Protocol (STP):Provides a single path between end stations, avoiding and
eliminating loops.
‧ Normal -- Rapid Spanning Tree Protocol (RSTP) : Detects and uses of network topologies that provide faster
spanning tree convergence, without creating forwarding loops.
‧ Extension – Multiple Spanning Tree Protocol (MSTP) : Defines an extension to RSTP to further develop the
usefulness of virtual LANs (VLANs). This "Per-VLAN" Multiple Spanning Tree Protocol configures a separate
Spanning Tree for each VLAN group and blocks all but one of the possible alternate paths within each Spanning
Tree.
The STP System Configuration screen in Figure 4-7-4 appears.
Figure 4-7-4: STP Bridge Configuration page Screenshot
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User's Manual of SGS-5220 Series