i have following situation,
1.I have two different ISP and Two different public ip which are connected to Cisco 1841 router with Serial Intreface.
2.I have One cisco ASA 5510 which are connected to Cisco 1841 router.
3.I am looking Loadbalacing so where we need to plan NAT in Cisco ASA or Cisco 1841 Router.
Now i want to make high availablity network, if one ISP link is down second ISP will autometic should be up.
Please suggest me what we need to do??