BGP FlowSpec: IPv4

This feature introduces BGP flow specification, where BGP can carry flow-specification network layer reachability information (NLRI) messages. By propagating firewall filter information as part of BGP, you can propagate firewall filters against denial-of-service (DoS) attacks dynamically across autonomous systems. 

This feature does not support the following match conditions: 

• ICMP codes alone [inet/inet6] 
• Source/destination prefix with offset for inet6 
• Flow label for inet6 
• Fragment for inet6 

 This feature also does not support the Traffic Marking action.