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Slashdot Asks: How Can We Prevent Packet-Flooding DDOS Attacks? (oceanpark.com)

Just last month Brian Krebs wrote "What appears to be missing is any sense of urgency to address the DDoS threat on a coordinated, global scale," warning that countless ISPs still weren't implementing the BCP38 security standard, which was released "more than a dozen years ago" to filter spoofed traffic. That's one possible solution, but Slashdot reader dgallard suggests the PEIP and Fair Service proposals by Don Cohen: PEIP (Path Enhanced IP) extends the IP protocol to enable determining the router path of packets sent to a target host. Currently, there is no information to indicate which routers a packet traversed on its way to a destination (DDOS target), enabling use of forged source IP addresses to attack the target via packet flooding... Rather than attempting to prevent attack packets, instead PEIP provides a way to rate-limit all packets based on their router path to a destination.
I've also heard people suggest "just unplug everything," but on Friday the Wall Street Journal's Christopher Mim suggested another point of leverage, tweeting "We need laws that allow civil and/or criminal penalties for companies that sell systems this insecure." Is the best solution technical or legislative -- and does it involve hardware or software? Leave your best thoughts in the comments. How can we prevent packet-flooding DDOS attacks?

2 of 351 comments (clear)

  1. Ineffective by DeathToBill · · Score: 5, Informative

    Technical measures that prevent address spoofing are quickly becoming obsolete anyway; AFAICT, the recent attacks on Krebbs and Dyn, the two biggest DDoS attacks ever, didn't use spoofed source addresses. A spoofed address is only useful in an amplification attack, where you send a small request which provokes a much larger response; then if you don't spoof the source address, you get a huge firehose of responses coming at you and it's you that gets DDoSed, not the target.

    In this case, the attackers didn't bother spoofing source addresses, because they didn't use an amplification attack; they just used a huge botnet all making ostensibly-valid requests and each device dealing with the response individually. It looks like the only way we have of preventing this sort of attack is to make the devices secure - easier said than done.

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  2. Re:Make ISPs at the source responsible by ledow · · Score: 5, Informative

    They are.

    No source addresses were faked here.

    Just millions of "genuine", unfaked connections.

    That's the "new" part of this attack. It's not trying to pretend it's anything that it isn't. It's literally just millions of devices requested advertised services and responding to their responses in the correct manner.

    Imagine a DDoS of just asking for Wikipedia pages. It's hard to combat because you have no way to distinguish it from just a sudden surge of genuine traffic.