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Catalyst 3550 Multilayer Switch Software Configuration Guide
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Chapter 1 Overview
Features
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Terminal Access Controller Access Control System Plus (), a proprietary feature for managing network
security through a TACACS server
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Remote Authentication Dial-In User Service (RADIUS), which provides detailed accounting information and flexible
administrative control over authentication and authorization processes
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 classification (classification based on information
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
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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 only)
Out-of-Profile
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Out-of-profile markdown for packets that exceed bandwidth utilization limits
Egress Policing and Scheduling of Egress Queues
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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 strict priority queue and the other three queues for WRR. The
strict priority queue must be empty before the other three queues are serviced. You can use the strict priority queue for
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
Layer 3 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 scalable, routed backbones:
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Routing Information Protocol (RIP) versions 1 and 2
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Open Shortest Path First (OSPF)
–
Interior Gateway Routing Protocol (IGRP) and Enhanced IGRP (EIGRP)
•
IP routing between VLANs (inter-VLAN routing) for full Layer 3 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 or more VLANs
•
Static IP routing for manually building a routing table of network path information
•
Equal-cost routing for load balancing and redundancy
Table 1-1
Features (continued)
