This is an old revision of the document!
http://ubuntu-tutorials.com/2007/09/02/network-security-with-tcpwrappers-hostsallow-and-hostsdeny/
gate# ldd /usr/sbin/sshd | grep wrap gate# cat /etc/hosts.allow
ALL: 127.0. sshd: 192.168.5.10
gate# cat /etc/hosts.deny
ALL:ALL