Chapter 1
Overview
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Note
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Note
VLAN Features
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Note
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OL-26520-01
Optional spanning-tree features available in PVST+, rapid-PVST+, and MSTP mode:
Port Fast for eliminating the forwarding delay by enabling a port to immediately change from
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the blocking state to the forwarding state
BPDU guard for shutting down Port Fast-enabled ports that receive bridge protocol data units
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(BPDUs)
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BPDU filtering for preventing a Port Fast-enabled port from sending or receiving BPDUs
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Root guard for preventing switches outside the network core from becoming the spanning-tree
root
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Loop guard for preventing alternate or root ports from becoming designated ports because of a
failure that leads to a unidirectional link
Flex Link Layer 2 interfaces to back up one another as an alternative to STP for basic link
redundancy
To use Flex Links, the switch must be running the LAN Base image.
Link-state tracking to mirror the state of the ports that carry upstream traffic from connected hosts
and servers, and to allow the failover of the server traffic to an operational link on another Cisco
Ethernet switch.
To use Link-state Tracking, the switch must be running the LAN Base image.
Support for up to 255 VLANs for assigning users to VLANs associated with appropriate network
resources, traffic patterns, and bandwidth
Up to 64 VLANs are supported when the switch is running the LAN Lite image.
Support for VLAN IDs in the 1 to 4094 range as allowed by the IEEE 802.1Q standard
VLAN Query Protocol (VQP) for dynamic VLAN membership
IEEE 802.1Q trunking encapsulation on all ports for network moves, adds, and changes;
management and control of broadcast and multicast traffic; and network security by establishing
VLAN groups for high-security users and network resources
Dynamic Trunking Protocol (DTP) for negotiating trunking on a link between two devices and for
negotiating the type of trunking encapsulation (IEEE 802.1Q) to be used
VLAN Trunking Protocol (VTP) and VTP pruning for reducing network traffic by restricting
flooded traffic to links destined for stations receiving the traffic
Voice VLAN for creating subnets for voice traffic from Cisco IP Phones
Catalyst 2960 and 2960-S Switches Software Configuration Guide, Release 15.0(1)SE
Features
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