Chapter 1: Key Concepts > Using FortiDDoS ACLs

Using FortiDDoS ACLs

You can configure access control lists (ACLs) to deny known attacks and unwarranted traffic. For example, in a data center environment, you can use ACLs to protect the router from getting overloaded by floods from known attacks.

The ACLs are part of the core hardware architecture, so they do not add to latency through the device when you enable or disable them.

FortiDDoS enforces a Global ACL that applies to all traffic, and SPP ACLs that are applied after traffic has been sorted into an SPP.

The Global ACL features include:

It is possible for traffic to be denied based on multiple Global ACL rules, but only one deny reason-code is logged. The reason-code is based on the following order of precedence.

  1. Anti-spoofing
  2. Source IP address
  3. GeoLocation
  4. IP Reputation

You can configure additional ACLs per SPP. The SPP ACL rules can be based on source IP address, service, or Layer 7 parameter.

The following table summarizes the traffic parameters you can use to enforce an ACL.

 Table 5:   ACL parameters

Parameter ACL
Layer 3
Any protocol (up to 256) SPP
Fragment SPP
IP netmask or address (up to 4 billion) Global, SPP
Geolocation (countries and regions), anonymous proxy, satellite provider Global
IP-reputation (based on data from external public sources) IP Reputation (subscription)
Layer 4
TCP port (up to 64k) SPP
UDP port (up to 64k) SPP
ICMP type/code (up to 64k) SPP
Layer 7
URLs (up to 32k) SPP
Host (512) SPP
Referer (512) SPP
Cookie (512) SPP
User-Agent (512) SPP
DNS-All SPP
DNS-Fragment SPP
DNS-MX SPP
DNS-Zone-Transfer SPP
Restrict DNS Queries to specific subnets SPP
DNS Blacklisted Domains Global
DNS Blacklisted IPv4 Addresses Global