BGP is classified as a path-vector routing protocol, and it makes routing decisions based on paths, network policies, or rule-sets configured by a network administrator. BGP may be used for routing within an autonomous system.
For the internet to work, internet service providers, data centers, and network providers advertise via the BGP routing protocol the IP addresses that they route and manage.
This is mostly a “trust-based system” and when a large ISP starts advertising routes for IP address ranges that they do not manage, it causes worldwide outages and performance issues.
Based on customer reports, CenturyLink appears to have made a mistake in the BGP routing, which led to today’s wide-scale issues. Basically, portions of the internet were not correctly routed.
Cloudhelix, a cloud hosting provider, also experienced the same outages and performance problems and issued an incident report claiming that CenturyLink confirmed a routing issue in their network, which was preventing BGP sessions from establishing correctly.
