Adding ACL on CATOS (6500)

Console> (enable) set ip permit 172.16.0.0 255.255.0.0 telnet
172.16.0.0 with mask 255.255.0.0 added to telnet permit list.

Console> (enable) set ip permit 172.20.52.42 255.255.255.224 snmp
172.20.52.42 with mask 255.255.255.224 added to snmp permit list.

To check:
Console> (enable) sh ip permit