Cisco Catalyst 2950 User Manual

Contents
xii
Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
78-11380-12
CHAPTER 13 Configuring STP 13-1
Understanding Spanning-Tree Features 13-1
STP Overview 13-2
Spanning-Tree Topology and BPDUs 13-2
Bridge ID, Switch Priority, and Extended System ID 13-3
Spanning-Tree Interface States 13-4
Blocking State 13-6
Listening State 13-6
Learning State 13-6
Forwarding State 13-6
Disabled State 13-7
How a Switch or Port Becomes the Root Switch or Root Port 13-7
Spanning Tree and Redundant Connectivity 13-8
Spanning-Tree Address Management 13-8
Accelerated Aging to Retain Connectivity 13-8
Spanning-Tree Modes and Protocols 13-9
Supported Spanning-Tree Instances 13-9
Spanning-Tree Interoperability and Backward Compatibility 13-10
STP and IEEE 802.1Q Trunks 13-10
Configuring Spanning-Tree Features 13-11
Default Spanning-Tree Configuration 13-11
Spanning-Tree Configuration Guidelines 13-12
Changing the Spanning-Tree Mode 13-13
Disabling Spanning Tree 13-14
Configuring the Root Switch 13-14
Configuring a Secondary Root Switch 13-16
Configuring the Port Priority 13-17
Configuring the Path Cost 13-18
Configuring the Switch Priority of a VLAN 13-20
Configuring Spanning-Tree Timers 13-20
Configuring the Hello Time 13-21
Configuring the Forwarding-Delay Time for a VLAN 13-22
Configuring the Maximum-Aging Time for a VLAN 13-22
Configuring Spanning Tree for Use in a Cascaded Stack 13-23
Displaying the Spanning-Tree Status 13-24

Cisco Catalyst 2950 Specifications

General

Forwarding Bandwidth	8.8 Gbps
Switching Capacity	13.6 Gbps
Forwarding Rate	6.6 Mpps
Weight	3.6 kg
RAM	16 MB
Flash Memory	8 MB
Operating Humidity	10% to 85% non-condensing
Uplink Ports	2 x 10/100/1000Base-T
Dimensions	4.4 cm x 44.5 cm x 24.2 cm
Remote Management Protocol	SNMP, Telnet, HTTP
Features	Quality of Service (QoS), VLAN support
Compliant Standards	IEEE 802.3, IEEE 802.3u, IEEE 802.1D, IEEE 802.1Q, IEEE 802.1p
Status Indicators	system
Operating Temperature	0 to 45°C
Ports	24 x 10/100 Ethernet ports
MAC Address Table Size	8, 192 entries
Power Supply	Internal 100-240V AC, 50-60Hz