VLAN using Public IP

[klept]

Hi Support,

i configured vlan with cisco switch, and it seems working using class C ip, but when i use or public IP provided by ISP it didn't work. WAN is directly connected to modem.

TIA!!!

[Guest]

i configured vlan with cisco switch, and it seems working using class C ip,

If this is done in the LAN it would be right. VLANs are also able to configured on the WAN side but more
common at all IP Internet accounts with serving different services providing TV, VOIP and Internet services
that will be spread into VLANs from the ISP side. In your case it would be right to use internally private IPs.

but when i use our public IP provided by ISP it didn't work. WAN is directly connected to modem.

Internet –- public IPs --- WAN Port - pfSense - LAN Port --- private IPs --- Switch --- LAN devices

What you want to realize in that case with static public IPs internally used? In normal or common use cases
this is not really wanted by the administrators. You can either try out to build a DMZ and place there the
devices such as servers and/or devices for the public access over the Internet. Or you will be able to set
up the static public IP address on the pfSense firewall directly and then route and port forward them to
the internal IP addresses of the servers in the DMZ. Would be more secure.

But what ever you try to do or realize, you should be providing more details over the entire use case and
your network topology.