Cấp phát IP

10.85.133.32/27

Subnest Mask: 255.255.255.224
IP có thể dùng: 10.85.133.33 đến 10.85.133.62 (bỏ 32; 63)

http://www.subnet-calculator.com/cidr.php

Ở router, thay vì 8 câu lệnh:
# Khi request (ping, HTTP...) từ router tới IP 66.100.50.1; 66.100.50.2; ...; 66.100.50.31 hãy sử dụng gateway 194.1.1.1
ip route 66.100.50.0 255.255.255.224 194.1.1.1
# Khi request (ping, HTTP...) từ router tới IP 66.100.50.33; 66.100.50.34; ...; 66.100.50.63 hãy sử dụng gateway 194.1.1.1
ip route 66.100.50.32 255.255.255.224 194.1.1.1
# ...
ip route 66.100.50.64 255.255.255.224 194.1.1.1
ip route 66.100.50.96 255.255.255.224 194.1.1.1
ip route 66.100.50.128 255.255.255.224 194.1.1.1
ip route 66.100.50.160 255.255.255.224 194.1.1.1
ip route 66.100.50.192 255.255.255.224 194.1.1.1
ip route 66.100.50.224 255.255.255.224 194.1.1.1

Hãy gõ:
ip route 66.100.50.0 255.255.255.0 194.1.1.1