cisco ccna 200-301 dump

cisco ccna 200-301 dump.21.02 ACL Basic Configuration Two-Minute Sprint21.03 ACL Type Self-Test QuestionsThe previous chapters discussed routing protocols and their basic configuration. By default, once routing is configured, the router will allow any packets to be transmitted from one interface to another. For security or traffic policy reasons, you might want to implement a traffic transmission restriction policy. Cisco provides Access Control Lists (ACLs) that allow you to restrict the flow of traffic between interfaces. ACLs are a powerful feature of Cisco IOS; in fact, Cisco supports the use of ACLs for other protocols besides IP protocols, such as Interconnection Network Packet Exchange (IPX), AppleTalk. layer 2 traffic, and so on. This chapter only describes IPACLs.Authentication Cultivation Lists 21.0121.1 Overview of ACLsThe primary use of an ACL is to filter traffic entering or leaving an interface, but it has other uses, such as restricting remote access to IOS devices via virtual type terminals (VTYs), filtering routing information, specifying the priority of traffic in queuing techniques, triggering phone calls in dial-on-demand routing (DDR), modifying the administrative distance of routes, and specifying traffic to be protected using IPsecVPN for protected traffic, and so on. This chapter covers restricting traffic delivery on the router only.Exam Essentials ACLs can be used to filter traffic passing through an IOS device and can also be used to filter remote access to the IOS over VTY lines21.1.1 DefinitionAn ACL is basically a set of commands grouped together by number or name that are used to filter traffic entering or leaving an interface. ACL commands specify which traffic is allowed through and which traffic is prohibited. ACLs are created in global configuration mode.After you create a set of ACL statements, you must activate them. To filter traffic between interfaces. activate ACLo in interface subconfiguration mode The interface here can be a physical interface such as ethemetO or serialO,or a logical interface such as ethemetO. 1 or serialO.lo When activating an ACL on an interface. you must specify which direction of traffic is to be filtered.