ash73 wrote

Model : TD-W9980, Hi, is it possible to assign clients connected to the guest network to a different IP range with DHCP? It's a TD-W9980.

I would like to assign some specific firewall rules to these clients, so they need a different LAN host (IP range).

NO... it´s a device SOHO (Small Office-Home Office) It does not have the characteristics of a high-end or professional router, since it only has a single DHCP server ...
I am afraid that it will be impossible to do it with this equipment and / or brand ...

What you can do is do an IP-Binding and exercise control over these specific ip either by control of bandwidth or by firewall through the MAC Address of these devices ...

Regards...

Found several solutions; address reservation of known mac addresses, everything else gets a dynamic ip and dhcp range is treated as a separate lan host with firewall rules. Or treat 2.4/5 wireless as separate lan hosts using interface grouping, or an AP plugged into a LAN port in a separate interface group, then everything can have dynamic ip.

NB I found guest network is not secure with IPSec VPN active.