Share WAN w/ multiple pub ips thru multiple interfaces (almost like SOHO router)

[elementalwindx]

On the section of this picture I've attached I'm trying to attach our VOIP phone server to the PFsense rather than directly to the edge so I can monitor bandwidth and such. I also want to provide a method for failover options.

I have 5 physical adapters in this pfsense box, 2 for incoming WAN each having 10 public IPs and 3 other NICs for various things (Wifi/General LAN/Phone server)

How can I go about getting this to work so that the phone server uses one of the available static ip's to go thru the WAN connection?

Thanks.

[elementalwindx]

I'm thinking this might involve virtual IPs, but I want the phone server to be DMZ as if it's an edge device.