Simwood's blog has a few articles from the past couple weeks with commentary on the attacks to voip providers in the UK. https://blog.simwood.com/2021/09/voip-ddos-fail-to-prepare/

On Tue, Sep 21, 2021 at 2:31 PM Mike Hammett <nanog@ics-il.net> wrote:
As many may know, a particular VoIP supplier is suffering a DDoS. https://twitter.com/voipms

Are your garden variety DDoS mitigation platforms or services equipped to handle DDoSes of VoIP services? What nuances does one have to be cognizant of? A WAF doesn't mean much to SIP, IAX2, RTP, etc.



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Mike Hammett
Intelligent Computing Solutions
http://www.ics-il.com

Midwest-IX
http://www.midwest-ix.com