SLB features should help for load balanicng the network traffic from ISP.
Server load balancing (SLB) on the ACE provides the following features:
⢠Network traffic policies for SLB
⢠Real servers and server farms
⢠Health monitoring through probes, as well as TCL scripts
⢠Stickiness (connection persistence)
⢠Firewall load balancing (FWLB) to load-balance traffic from the Internet through a firewall to a data center or intranet
For more information, see the Cisco Application Control Engine Module Server Load-Balancing Configuration Guide.
http://www.cisco.com/en/US/docs/interfaces_modules/services_modules/ace/v3.00_A1/configuration/slb/guide/preface.html