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7
Spanning Tree Algorithm
This chapter describes the following basic topics:
◆
– Configures detection and response to loopback BPDUs.
◆
– Configures global bridge settings for STP, RSTP and
MSTP.
◆
– Configures interface settings for STA, including
priority, path cost, link type, and designation as an edge port.
◆
– Sets the VLANs and associated priority assigned to
an MST instance
◆
– Configures interface settings for MSTP, including
priority and path cost.
Overview
The Spanning Tree Algorithm (STA) 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 (that is, an STA-compliant
switch, bridge or router) in your network to ensure that only one route exists
between any two stations on the network, and provide backup links which
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)
STP
– STP uses a distributed algorithm to select a bridging device (STP-compliant
switch, bridge or router) that serves as the root of the spanning tree network. It
selects a root port on each bridging device (except for the root device) which incurs
the lowest path cost when forwarding a packet from that device to the root device.
Then it selects a designated bridging device from each LAN which incurs the lowest
path cost when forwarding a packet from that LAN to the root device. All ports
connected to designated bridging devices are assigned as designated ports. After
determining the lowest cost spanning tree, it enables all root ports and designated
ports, and disables all other ports. Network packets are therefore only forwarded
between root ports and designated ports, eliminating any possible network loops.
Summary of Contents for GTL-2881
Page 34: ...Section I Getting Started 34 ...
Page 48: ...Section II Web Configuration 48 Unicast Routing on page 651 ...
Page 151: ...Chapter 4 Interface Configuration VLAN Trunking 151 Figure 69 Configuring VLAN Trunking ...
Page 152: ...Chapter 4 Interface Configuration VLAN Trunking 152 ...
Page 230: ...Chapter 8 Congestion Control Automatic Traffic Control 230 ...
Page 596: ...Chapter 14 Multicast Filtering Multicast VLAN Registration for IPv6 596 ...
Page 620: ...Chapter 15 IP Configuration Setting the Switch s IP Address IP Version 6 620 ...
Page 672: ...Section III Appendices 672 ...
Page 678: ...Appendix A Software Specifications Management Information Bases 678 ...
Page 688: ...Appendix C License Statement GPL Code Statement Notification of Compliance 688 ...
Page 696: ...Glossary 696 ...
Page 706: ...GTL 2881 GTL 2882 E112016 ST R01 ...