cisco ccna 200-301 en espa?ol

cisco ccna 200-301 en espa?ol.. Inbound (traffic entering the interface from outside) .. Outbound (before the traffic leaves the interface).For inbound ACLs, the IOS compares the packets with the ACL before forwarding them to other interfaces; for outbound ACLs, the IOS forwards the received packets to the outbound interface and compares the packets with the ACL.One limitation of ACLs is that they cannot filter traffic that originates at the current router. For example, if you perform ping or traceroute on a router, or Telnet from a router to another device, the ACL applied to that router's interface will not filter that outbound traffic. However, if an external device attempts to ping, traceroute, or Telnet to the router, or to a remote destination device via the router, the router is able to filter these packets.For an inbound ACL, the IOS processes it before performing other processing; for an outbound ACL, the IOS forwards the packet to the outbound interface and then processes it. Outbound ACLs cannot be used to filter traffic that originates on the current router.Chapter 21 Access Control Lists 55121.1.2 TypesThere are two types of ACLs: numbered ACLs and named ACLoACLs are of a type that determines how the router will refer to it; the number and name are similar to index values. A numbered ACL has a number that is unique among all ACLs; a named ACL has a name that is unique among all named ACLs. The router uses these ACLs to filter traffic.Both ACLs support two types of filtering: standard and extended. Standard IP ACLs can only filter based on the source IP address of the packet, while Extended IP ACLs can filter based on the source and destination IP addresses in the packet, the IP protocol (TCP, UDP, ICMP, etc.), and protocol information (such as TCP/UDP source and destination ports or ICMP message types). Very accurate filtering is possible using extended ACLs, for example, to filter Telnet sessions from a specific user PC to a remote Telnet server. Standard ACLs do not have as fine a granularity of filtering. When using a standard ACL, traffic from a specific source device is either allowed to pass through both of them or prohibited. Table 21.1 compares these two types of IP traffic filtering.Table 21.1 Comparison of Standard ACLs and Extended ACLs