Greetings, cisco's new Committed Access Rate feature lets you do real QoS rate limiting (as opposed to traffic shaping) with access lists. CAR could be implemented on either ingress/egress interfaces to limit bandwidth usage by ICMP to something safe like 5MBits. This would prevent an incoming ICMP flood from consuming your aggregation links, while it still might inconvenience a T1 customer. If placed on the outgoing access-list it can prevent your network from originating unfriendly amounts of ICMP. CAR can either discard or decrease the priority of the offending traffic. A couple of questions: I am unfamiliar with what tier 1 providers use as aggregation routers(routers their T3+ customers connect to). Due to CAR's potentially CPU intensive nature (when dealing with access-list based traffic limiting compared to address based limiting), would an "ICMP permit with exceed-action drop" filter constitute an unacceptable load on the CPU and memory of these routers? If I only had 1 multi-megabit transit pipe, is it reasonable(in the future) of me to ask/require my upstream provider to protect my pipe from being wasted by large amounts of ICMP? If I only put it on my side, the pipe still gets wasted. Are there any other vendors who offer a similar feature without the use of ATM? Thank you. Marko