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No. What we need are new techniques for creating back-pressure to all the routers which are forwarding on this type of attack. The issue is that our Routing technology does not give downstream nodes any way to push back on the flood of packets.

Cisco could step up to the plate here. And no, I'm not talking about firewalls. We need newer ICMP type packets to create this back-pressure, so that we can stop floods like this.



>"What we need are new techniques for creating back-pressure to all the routers which are forwarding on this type of attack"

What is this type of attack? TCP/UDP/ICMP has no notion of of a compromised host. Or even that it was crafted packet.

Back pressure already exists in TCP, see slow-start and window sizes, flow control is part of the "control part". When a router's porst buffers are full the router drops the packets on the floor. It does not do further processing of those packets.

What would ICMP do here? If I have a million compromised hosts and each sends a single SYN packet towards a destination host, how would ICMP help?

">Cisco could step up to the plate here" What would Cisco do? Cisco doesn't control the ICMP protocol.

I think you are not understanding ICMP. The job of ICMP is to report error conditions. ICMP serves as a helper to IP which is itself unreliable and has no form of error control or checking. A router or host being overrun is not a network error condition it is a resource condition. No ICMP type is ever going to be able to stop a host from originating UDP/TCP/ICMP towards a destination. Even if it could you would just overwhelm it in the outbound direction by replying to potentially millions of hosts.


It looks like we used to have something similar but it got deprecated. https://tools.ietf.org/html/rfc6633


I was a big fan of ICMP Source Quench in the early 1980s, but it wouldn't help now. It doesn't have authentication.




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