This feature would allow flexible and fine-grained IP-based access control on [sub]domain level, i.e.:
```
set load-balancing reverse-proxy service my-new-api backend 'new-bk-01'
set load-balancing reverse-proxy service my-new-api mode 'http'
set load-balancing reverse-proxy service my-new-api port '443'
set load-balancing reverse-proxy service my-new-api rule 10 domain-name 'example.com'
set load-balancing reverse-proxy service my-new-api rule 10 allow ip '10.10.10.0/24'
set load-balancing reverse-proxy service my-new-api rule 10 allow ip '10.10.11.0/24'
set load-balancing reverse-proxy service my-new-api rule 20 domain-name 'new.example.com'
set load-balancing reverse-proxy service my-new-api rule 20 deny ip !'10.10.12.0/24'
set load-balancing reverse-proxy service my-new-api ssl certificate 'my-new-api-cert'
set load-balancing reverse-proxy backend bk-01 balance 'round-robin'
set load-balancing reverse-proxy backend bk-01 mode 'http'
set load-balancing reverse-proxy backend bk-01 server srv01 address '192.0.2.11'
set load-balancing reverse-proxy backend bk-01 server srv01 port '80'
```
the rule 10 in the example above would **allow** access to //example.com// only for two subnets(//10.10.10.0/24// and //10.10.11.0/24//), while rule 20 would **deny** access to //new.example.com// for everything but //10.10.12.0/24//.