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Catalyst 3550 Multilayer Switch Software Configuration Guide
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Chapter1 Overview
Features
Terminal Access Controller Access Control System Plus (TACACS+), a proprietary feature for managing network
security through a TACACS server
Remote Authentication Dial-In User Service (RADIUS), which provides detailed accounting information and flexible
administrative control over authentication and authorization proce sses
Quality of Service and Class of Service
Classification
IP type-of-service/Differentiated Services Code Point (IP TOS/DSCP) and 802.1P class of service (CoS) marking
priorities on a per-port basis for protecting the performance of mission-critical applications
IP TOS/DSCP and 802.1P CoS marking based on flow-based packet classific ation ( classi fica tion ba sed o n in for mat ion
in the MAC, IP, and TCP/UDP headers) for high-performance quality of service at the network edge, allowing for
differentiated service levels for different types of network traffic and for prioritizing mission-critical traffic in the
network
Policing
Traffic-policing policies on the switch port for managing how much of the port bandwidth should be allocated to a
specific traffic flow
Aggregate policing for policing traffic flows in aggregate to restrict specific applications or traffic flows to metered,
predefined rates
Up to 128 policers on ingress Gigabit-capable Ethernet ports
Up to eight policers on ingress 10/100 ports
Up to eight policers per egress port (aggregate policers onl y)
Out-of-Profile
Out-of-profile markdown for packets that exceed bandwidth utilization limits
Egress Policing and Scheduling of Egress Queues
Four egress queues on all switch ports. These queues can either be configured with the Weighted Round Robin (WRR)
scheduling algorithm or configured with one queue as a stri ct pri orit y que ue an d t he ot her thre e qu eues for W RR. The
strict priority queue must be empty before the other th ree q ueue s a re se rv iced . You can use the strict prior i ty q ue ue fo r
mission-critical and time-sensitive traffic.
Tail drop and Weight Random Early Detection (WRED) techniques for avoiding congestion on Gigabit Ethernet ports;
tail drop for congestion avoidance on Fast Ethernet ports
Layer3 Support
Note These features requires the enhanced multilayer software image.
Hot Standby Router Protocol (HSRP) for Layer 3 router redundancy
IP routing protocols for load balancing and for constructing sca la ble, rout ed backb one s:
Routing Information Protocol (RIP) versions 1 and 2
Open Shortest Path First (OSPF)
Interior Gateway Routing Protocol (IGRP) and Enhanced IGRP (EIGRP)
IP routing between VLANs (inter-VLAN routing) for full Layer3 routing between two or more VLANs, allowing each
VLAN to maintain its own autonomous data-link domain
Fallback bridging for forwarding non-IP traffic between two o r more VLA Ns
Static IP routing for manually building a routing table of network path information
Equal-cost routing for load balancing and redundancy
Table1-1 Features (continued)