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toast0yesterday at 3:21 PM2 repliesview on HN

> As the internet gets more users and more devices connected, the ratio of DDoS volume to a single connections volume will only get larger.

I'm not sure if that's the case. Large volumetric DDoS records have been increasing, but connection bandwidths have also been increasing.

7 tbps is a lot of traffic, but it only takes 7,000 nodes with 1G symetric connections to do it. Botnet sizes don't seem to be getting that much bigger.

The basic solution to volumetric DDoS is to get a bigger pipe; this works, kind of, but it's hard to get 7 Tbps of downstream capacity, and you need to be careful that you don't become a 7 Tbps reflector.

The more scalable way is using BGP to drop traffic before it gets to you. Depending on your relationship with your hosting facility and their ISPs or your ISPs, it's often pretty easy to get packet to a given IP dropped one network before yours. Ocassionally, those blocks could propagate, and things like BGP Flow Spec promise more specific filtering... dropping all packets to an attacked IP mitigages the attack for the rest of the IPs on the path, but dropping all UDP to an attacked IP might get all the attack traffic and let most non-attack traffic through... More specific rules are possible if you wanted to try to let DNS and HTTP/3 survive while being attacked.

To work against a 45 second attack, BGP based measures need a lot of automation.


Replies

dale_huevoyesterday at 4:38 PM

You don't think the proliferation of inexpensive dogshit IoT products from the Far East, running already-10-years-out-of-date versions of Linux (bonus if it has a hidden Telnet daemon with hardcoded root password!), hooked to ever-expanding 1Gbps residential fibre lines, has anything to do with it?

This represents like 75% of surveillance camera systems out there btw.

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