Cisco Ethernet switch, Installation Manual

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v
Redundancy
– Link state tracking to mirror the state of the external ports on the internal
Ethernet links and to allow the failover of the processor blade traffic to an
operational external link on a separate Cisco Ethernet switch.
– UniDirectional link detection (UDLD) on all Ethernet ports for detecting
and disabling unidirectional links caused by port faults
– IEEE 802.1D Spanning Tree Protocol (STP) for redundant backbone
connections and loop-free networks
– IEEE 802.1s Multiple STP (MSTP) for grouping VLANs into a
spanning-tree instance, and provided for multiple forwarding paths for
data traffic and load balancing
– IEEE 802.1w Rapid STP (RSTP) for rapid convergence of the spanning tree
by immediately transitioning root and designated ports to the converting
state
– Optional spanning-tree features available in the PVST+, rapid PVST+, and
MSTP modes
v VLAN support
– Support for 250 port-based VLANs for assigning users to VLANs
associated with the applicable network resources, traffic patterns, and
bandwidth.
– Support for up to 4094 VLAN IDs to enable service provider networks to
support the number of VLANs allowed by the IEEE 802.1Q standard.
– IEEE 802.1Q trunking protocol 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.
– VLAN Membership Policy Server (VMPS) for dynamic VLAN
membership.
– VLAN Trunking Protocol (VTP) pruning for reducing network traffic by
restricting flooded traffic to links destined for stations receiving the traffic.
– Dynamic Trunking Protocol (DTP) for negotiating trunking on a link
between two devices and for negotiating the type of trunking
encapsulation (802.1Q) to be used.
– Voice VLAN for creating subnets for voice traffic from Cisco IP phones
– VLAN 1 minimization to reduce the risk of spanning-tree loops or storms
by enabling VLAN 1 to be disabled on any individual VLAN trunk link.
With this feature enabled, no user traffic is sent or received. The switch
CPU continues to send and receive control protocol frames.
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Cisco Systems Intelligent Gigabit Ethernet Switch Module: Installation Guide