IXP

An Internet Exchange Point (IXP) is a physical infrastructure that enables different Internet service providers, content networks, and other organizations to exchange traffic locally, at reduced cost and with lower latency. By facilitating direct interconnection, IXPs help keep a portion of Internet traffic within the local or regional network, improving performance and reducing dependence on upstream providers.

Most IXPs operate as neutral facilities that provide a shared switching fabric, typically based on Ethernet. Participants connect to the IXP’s switching LANs and establish Border Gateway Protocol (BGP) sessions to exchange routing information. Route servers are often used to simplify peering by enabling many bilateral relationships with fewer configurations. Traffic exchange occurs at Layer 2, while each participant’s routers make the final routing decisions. Public peering is common, but private interconnections between two networks can also be placed inside an IXP facility.

IXPs are usually managed by non-profit associations, membership organizations, or commercial operators. They maintain policies that govern who can participate, how peering is established, and how traffic is managed. IXPs exist worldwide, with notable examples operating multiple points of presence and hosting hundreds of member networks, including large Internet providers, content delivery networks, and cloud services.

Benefits of IXPs include lower transit costs, reduced latency, higher available bandwidth, and greater resilience through local routing. However, not all traffic is routed through an IXP; networks may choose selective peering or private interconnects for certain connections.

Security and governance considerations include preventing route leaks, misconfigurations, and abuse. Many IXPs participate in the MANRS initiative, implement routing policies and filtering, and monitor BGP sessions to maintain stable and secure interconnections.