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Vectel
Support/Landline and VoIP

Phones dead, PBX unreachable, looks like a network attack

DDoS on SIP port happens, especially with open 5060 on a static IP.

Try this first

  1. 1Firewall: only allow provider IPs on ports 5060/5061
  2. 2fail2ban on PBX, ban IP after X failed REGISTERs
  3. 3Use TLS on 5061 instead of UDP 5060, fewer scan attacks
  4. 4DDoS protection at ISP or via cloud SBC

When to bring us in

Persistent DDoS? Temporarily fall back to mobile, then SBC behind anycast DDoS.

See also

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