Standard ACL and extended ACL application
Access Control List (ACL)
Reading a third layer, the fourth layer header information
Good planning of the packet filtering based on predefined
Access Control Lists in the direction of application interfaces
A: the router has been processed, is leaving the packet router interface
Into: packet has arrived at the router interface, the router will be processed
Standard Access Control Lists
Filtering packets based on source IP address
Standard access control list ACL number from 1 to 99
Extended Access Control Lists
Filtering packets based on IP address, destination IP address, specify the protocol, and port flags
Extended access control list ACL number from 100 to 199
Router # show access-list # view ACL table
Router (config) # Access-List . 1 the permit 192.168 . 1.0 0.0 . 0.255 # segment by allowing 192.168.1.0 Router (config) #access -list . 1 the permit 192.168 . 2.2 0.0 . 0.0 # 192.168.2.2 is not allowed by the Router (config) #access -list 1 deny Host 192.168.2.2 through 192.168.2.2 are not allowed #
Router (config) # access-lisr 1 permit any # allow other network traffic