Cisco 2950 Software Configuration Guide - Page 535
Configuring Network Security with ACLs, Network Security with ACLs
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29 C H A P T E R Configuring Network Security with ACLs This chapter describes how to configure network security on a Catalyst 2950 or Catalyst 2955 switch by using access control lists (ACLs), which are also referred to in commands and tables as access lists. You can create ACLs for physical interfaces or management interfaces. A management interface is defined as a management VLAN or any traffic that is going directly to the CPU, such as SNMP, Telnet, or web traffic. You can create ACLs for management interfaces with the standard software image (SI) or the enhanced software image (EI) installed on your switch. However, you must have the EI installed on your switch to apply ACLs to physical interfaces. Note An ACLs that applied is to a physical interface has a limitation of one mask, and certain keywords are not supported. For more information, see the "Guidelines for Applying ACLs to Physical Interfaces" section on page 29-5. Note For complete syntax and usage information for the commands used in this chapter, refer to the command reference for this release and the "Configuring IP Services" section of the Cisco IOS IP and IP Routing Configuration Guide, Cisco IOS Release 12.1 and the Cisco IOS IP and IP Routing Command Reference, Cisco IOS Release 12.1. This chapter consists of these sections: • Understanding ACLs, page 29-2 • Configuring ACLs, page 29-6 • Displaying ACL Information, page 29-21 • Examples for Compiling ACLs, page 29-23 You can configure ACLs by using the Cluster Management Suite (CMS) or through the command-line interface (CLI). Refer to the CMS online help for step-by-step configuration procedures through CMS. For information about accessing and using CMS, see Chapter 4, "Getting Started with CMS." You can also use the security wizard to filter inbound traffic on the switches. Filtering can be based on network addresses, TCP applications, or User Datagram Protocol (UDP) applications. You can choose whether to drop or to forward packets that meet the filtering criteria. To use this wizard, you must know how the network is designed and how interfaces are used on the filtering device. Refer to the security wizard online help for step-by-step configuration procedures about using this wizard. 78-11380-10 Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide 29-1
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