IS-IS Extensions for Flow Specification
Dissemination of the Traffic flow information was first introduced in the BGP protocol [RFC5575]. FlowSpec rules are used to distribute traffic filtering rules that are used to filter Denial-of-Service (DoS) attacks. For the networks that only deploy an IGP (Interior Gateway Protocol) (e.g., IS-IS), it is required that the IGP is extended to distribute Flow Specification or FlowSpec rules. This document discusses the use cases for distributing flow specification (FlowSpec) routes using IS-IS. Furthermore, this document defines a new IS-IS FlowSpec Reachability TLV encoding format that can be used to distribute FlowSpec rules, its validation procedures for imposing the filtering information on the routers, and a capability to indicate the support of FlowSpec functionality.