BGP ORIGIN Attribute Manipulation and Its Impact on the Internet
How manipulation of the BGP ORIGIN attribute affects global internet traffic.
1BGP and the ORIGIN Attribute
Border Gateway Protocol (BGP) is the core routing protocol of the internet. The ORIGIN attribute indicates how a route was injected into BGP and can take three values: IGP, EGP, and INCOMPLETE. This attribute plays a critical role in routing decisions.
2Prevalence of ORIGIN Manipulation
Research shows that approximately 70% of observed routes have an ORIGIN value different from what was set by the originating AS. This manipulation aims to divert traffic to specific networks for revenue gain.
3ORIGIN's Role in Path Selection
The BGP path selection algorithm evaluates the ORIGIN value alongside factors like Local Preference and AS_PATH length. A lower ORIGIN value increases the route's selection probability, prompting ASes to manipulate it.
4RFC4271 and ORIGIN Rules
RFC4271 states that the ORIGIN attribute should only be set by the originating AS and not modified by others. However, this rule is frequently violated in practice.
5Commercial Motivations Behind Manipulation
Transit providers change the ORIGIN value to IGP to gain a competitive edge, attracting more traffic and revenue. This has led to an 'arms race' in internet routing.
6Community Awareness and Reactions
The RIPE 91 and LACNIC 45 meetings highlighted the widespread manipulation of ORIGIN. Public disclosure aims to encourage operators to comply with RFC standards.
7Experimental Research Methods
Researchers announced IPv4 and IPv6 prefixes with different ORIGIN values to study manipulation. Data from RIPE RIS and RouteViews was analyzed using BGPKIT.
8The Flattening of the Modern Internet
The internet's increasingly flat structure complicates BGP analysis, making it harder to detect and prevent behaviors like ORIGIN manipulation.
9Proposal to Deprecate ORIGIN
Rising ORIGIN manipulation led to an Internet-Draft recommending its deprecation. However, this proposal has since expired.
10Operators' Strategic Decisions
Rather than waiting for competitors to comply with RFCs, operators continue ORIGIN manipulation, causing instability in internet routing.
11The Future of the Internet and BGP
ORIGIN manipulation poses a serious threat to internet reliability and stability. Solving this issue requires community-wide collaboration and protocol improvements.
Original article: Cloudflare Blog — BGP ORIGIN Manipülasyonu ve İnternet Üzerindeki Etkileri