 add a third interface, its security level will typically be somewhere between these values. As of ASA/PIX version 7.x, you can have multiple interfaces with the same security level. Figure 28-1 shows a typical firewall with three interfaces: outside and inside interfaces, and a DMZ. Given this design, by default, traffic may flow in the following ways: From inside to outside. From inside to the DMZ. From the DMZ to the outside, but not to the inside. Traffic from outside may not flow to any other interface. Interfaces and Security Levels GO/O-outside Security Level - 0 Least secure G0/2-DMZ Security Level - 50 Most secure G0/1-inside Security Level - 100 Figure 28-1. ASA interface security levels You can completely override the interface security level by using access lists, SO don't fall into the trap of thinking these rules are set in stone. To manually assign a priority to an interface, use the security-level interface com- mand. For example, here I configure the inside interface: ASA-5540/GAD(config)# int go/o ASA-5540/GAD(config-if)# nameif inside ASA-5540/GAD(config-if)# security-level 100 And here I configure the outside interface: ASA-5540/GAD(config)# int g0/1 ASA-5540/GAD(config-if)# nameif outside ASA-5540/GAD(config-if)# security-level 0 These values are the defaults for an ASA firewall. To configure the third interface in Figure 28-1, use the following commands: ASA-5540/GAD(config)# int g0/2 ASA-5540/GAD(config-if)# nameif DMZ ASA-5540/GAD(config-if)# security-level 50 To configure the speeds and duplex modes of the interfaces, use the interface command: ASA-5540(config)# int go/o ASA-5540(config-if)# speed 100 ASA-5540(config-if)# duplex full Chapter 28: ASA Firewall Configuration In multicontext mode, interface characteristics can only be changed within the system context. See "Managing Contexts" on page 479 for more information. To see the status of your interfaces, use the show interface command. The output of this command is similar to that produced in IOS, though the output changes depending 