An Internet Exchange (often abbreviated as IX or IXP) is a physical infrastructure that allows multiple internet networks (such as Internet Service Providers, ISPs, and Content Delivery Networks, CDNs) to connect and exchange internet traffic with one another. Instead of routing traffic through third-party networks, direct interconnection via an IXP allows for faster, more efficient, and often more cost-effective data exchange.
Key features and benefits of an Internet Exchange include:
The IXP itself typically consists of network switches, routers, and the necessary infrastructure to support the many networks that connect to it. Each member network connecting to the IXP usually has its routing policy and decides which traffic it will route through the IXP and which connections it will establish (or "peer" with).
Peering at an IXP is typically governed by mutual agreements, which can be formal (paid peering) or informal (settlement-free peering). In the case of settlement-free peering, two networks agree to exchange traffic without payment, based on the mutual benefits of the connection.
In summary, an Internet Exchange Point (IXP) is a vital component of the internet's infrastructure, allowing networks to connect directly and exchange traffic, fostering improved performance, cost efficiencies, and the growth of the internet ecosystem.