I do not have Swisscom services, just plain Cablecom with multiple public IPs.
Previously, I had a Linux box ( IPCOP
http://www.ipcop.org/ ) that handled all 4 IPs that Cablecom gave me. The box was connected directly to the ISP modem ( VLAN ).
Later one, I had a
business router with several WAN ports ( and VLAN capability ) which was connected to a switch which was then connected to the ISP modem.

Most simply routers cannot handkle more than a single public IP unless flashed with an alternate firmware.