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BGP FlowSpec Rule Builder
Generate BGP FlowSpec rules for surgical DDoS traffic filtering. Define match criteria, select actions, and export ready-to-use configurations for ExaBGP, BIRD, GoBGP, or Cisco IOS-XR.
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BGP FlowSpec (RFC 5575) distributes traffic filtering rules via BGP. Instead of blackholing entire prefixes (RTBH), FlowSpec lets you surgically drop, rate-limit, or redirect specific traffic patterns — filtering by source/destination IP, protocol, port, packet length, DSCP, and TCP flags.
FlowSpec Match Types
Destination Prefix
The target IP or subnet being attacked. Usually your own prefix (e.g., 203.0.113.0/24). Required for most FlowSpec implementations.
Source Prefix
Filter by source IP or subnet of the attacker. Useful for known botnets or spoofed source ranges. Leave empty to match any source.
Protocol & Port
Match on IP protocol (TCP, UDP, ICMP) and destination/source port numbers. Essential for filtering amplification attacks targeting specific services.
Packet Length
Filter by IP packet size. Amplification attacks often have characteristic packet sizes (e.g., DNS responses >512 bytes, NTP monlist >440 bytes).
TCP Flags
Match specific TCP flag combinations: SYN, ACK, FIN, RST, PSH, URG. Critical for identifying SYN floods (SYN without ACK) or malformed packets.
Actions
Drop discards matching packets. Rate-limit throttles traffic to a specified bps. Redirect sends traffic to a scrubbing VRF for inspection.
Automate FlowSpec with Flowtriq
Flowtriq automatically generates and deploys FlowSpec rules when attacks are detected — no manual configuration needed. Our 4-level auto-escalation moves from local firewall to FlowSpec to RTBH to cloud scrubbing in seconds.
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