Product specifications
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Feature Benefit
Superior Redundancy for
Fault Backup
IEEE 802.1D Spanning
Tree Protocol
IEEE 802.1w Rapid Spanning
Tree Protocol
Per-VLAN Rapid Spanning
Tree Plus (PVRST+)
PortFast
UniDirectional Link Detection
(UDLD) and Aggressive UDLD
Switchport Autorecovery
BPDU Guard
Spanning Tree Root Guard
(STRG)
UplinkFast/BackboneFast
Ensures loop-free networks simplifies network configuration and improves fault tolerance.
Provides rapid spanning tree convergence independent of spanning tree timers and the benefit of
distributed processing.
Allows rapid spanning tree re-convergence on a per-VLAN spanning tree basis, without requiring the
implementation of spanning tree instances.
Transitions a port directly to forwarding state after linkup, allowing users to connect to the network in 2-3 seconds,
rather than waiting ~50 seconds for spanning tree to resolve.
Unidirectional links automatically detected and disabled to avoid problems such as spanning tree loops;
Aggressive Mode automatically retries the link periodically to see if it has returned to bidirectional.
Automatically attempts to re-enable a link that is disabled due to a network error (also known as
"errdisable recovery").
Shuts down Spanning-Tree Protocol PortFast-enabled interfaces when Bridge Protocol Data Units (BPDUs) are
received to avoid accidental topology loops.
Prevents edge devices not in the network administrator's control from becoming Spanning Tree Protocol root
nodes.
Ensure quick fail-over recovery enhancing overall network stability and reliability.
Bandwidth Availability
Per-port broadcast, multicast,
and unicast storm control
Per VLAN Spanning Tree Plus
(PVST+)
IEEE 802.1s Multiple Spanning
Tree Protocol (MSTP)
VLAN Trunking Protocol (VTP)
pruning
Internet Group Management
Protocol (IGMP) Snooping
IGMP immediate-leave
processing
Multicast VLAN Registration
(MVR)
Prevents faulty end stations from degrading overall systems performance.
Allows for Layer 2 load sharing on redundant links to utilize the full capacity of a redundant design.
Allows a spanning tree instance per VLAN, enabling Layer 2 load sharing on redundant links.
Limits bandwidth consumption on VTP trunks by limiting broadcast traffic only to trunk links required to reach the
destination devices.
Provides bandwidth-intensive multicast traffic to only the requestors, rather than flooding all ports. Support for
IGMP version 1 and 2.
Faster than normal multicast leave processing, this prunes out unnecessary multicast traffic immediately after a
leave request.
Allows multicast streams in a single networkwide multicast VLAN while subscribers remain in separate VLANs for
bandwidth and security reasons.
Quality of Service/Control
Advanced Quality of Service
Honor 802.1p class of
service (CoS)
Mark/override 802.1P CoS
per port
4 egress queues per port
Weighted Round Robin (WRR)
scheduling
Strict Priority scheduling
Ability to prioritize traffic and put it in different queues.
Network administrator can enforce QoS policies, and prevent users from abusing QoS settings.
Enables network traffic to be put into 4 different queues, depending on the CoS priority.
High priority queues can be allocated more time to send traffic. However, WRR also ensures lower priority queues
are not neglected.
Guarantees that the highest-priority packets are serviced ahead of all other traffic. Particularly useful
for time-sensitive applications like voice over IP.
Security
Network Management Security
VLAN1 minimization
TACACS+ and RADIUS
Authentication
Multilevel management levels
Secure Shell v2
Allows VLAN1 to be disabled on any individual VLAN trunk link.
Terminal Access Controller Access Control System Plus (TACACS+) and Remote Authentication Dial-In User
Service (RADIUS) authentication enable centralized control of switch administration and management.
Allows for 15 levels of switch management authorization, ranging from read-only to full read/write capabilities.
SSHv2 provides network security by encrypting administrator traffic during Telnet sessions. SSHv2 requires a
special cryptographic software image because of U.S. export restrictions.
Network Edge Security
IEEE 802.1x
IEEE 802.1x with VLAN
assignment
IEEE 802.1x with Guest VLAN
IEEE 802.1x and port security
IEEE 802.1x with voice VLAN
Private VLAN Edge
SPAN for IDS
MAC address notification
Allows dynamic, port-based security, providing user authentication.
Allows a dynamic VLAN assignment for a specific user regardless of where the user is connected.
Allows guests without 802.1x clients to have limited network access on the guest VLAN.
Provided to authenticate the port and manage network access for all MAC addresses, including those of the
client.
Permits an IP phone to access the voice VLAN irrespective of the authorized or unauthorized state of the port.
Provides security and isolation between switch ports, which helps ensure that users cannot snoop on other users'
traffic.
Bidirectional data support on the Switched Port Analyzer (SPAN) port allows Cisco Secure Intrusion Detection
System (IDS) to take action when an intruder is detected.
Allows administrators to be notified of users added to or removed from the network. Good for tracking location of