We are having a server with good CPU and RAM,so we are planning to do XEN virtualization on ubuntu 12.04 server to handle high traffic. The plan is to keep the host machine only to manage VMs(no NAT ing).

A New public IP will be assigned to that VM,For that i think we need a Bridge to external network(Since my Machine has only single ethernet card aliased with 4 different Pub IP's) Is it possible to create a bridge using aliased IP

single ethernet card aliased to 4 pub IPs

Do we need an additional Ethernet card to do Bridging.Only have ssh access to the machine. Any suggestions will be appreciated.