Creating Extended ACLs

Router(config)#access-list 110 permit tcp 172.16.0.0 0.0.0.255 192.168.100.0 0.0.0.255 eq 80	Read this line to say: HTTP packets with a source IP address of 172.16.0.x will be permitted to travel to destination address of 192.168.100.x
access-list	ACL command
110	Number is between 100 and 199, designating this as an extended IP ACL
permit	Packets that match this statement will be allowed to continue
tcp	Protocol must be TCP
172.16.0.0	Source IP address to be compared to
0.0.0.255	Wildcard mask
192.168.100.0	Destination IP address to be compared to
0.0.0.255	Wildcard mask
eq	Operand, means "equal to"
80	Port 80, indicating HTTP traffic
Router(config)#access-list 110 deny tcp any 192.168.100.7 0.0.0.0 eq 23	Read this line to say: Telnet packets with any source IP address will be dropped if they are addressed to specific host 192.168.100.7
access-list	ACL command
110	Number is between 100 and 199, designating this as an extended IP ACL
deny	Packets that match this statement will be dropped and discarded
tcp	Protocol must be TCP protocol
any	Any source IP address
192.168.100.7	Destination IP address to be compared to
0.0.0.0	Wildcard mask; address must match exactly
eq	Operand, means "equal to"
23	Port 23, indicating Telnet traffic