Peering is the agreement between two autonomous systems (ASes) — typically an ISP and a content provider, or two ISPs — to exchange traffic directly. The exchange happens either at an Internet Exchange Point (IXP) like AMS-IX in Amsterdam, LINX in London, DE-CIX in Frankfurt or Equinix Ashburn, or via a private network interconnect (PNI) — a direct cable between two networks. Peering can be settlement-free (both sides see roughly equal traffic value) or paid (one side pays the other).
For streaming, peering is why CDNs are so fast. When Akamai peers with Comcast, a viewer on Comcast in Philadelphia hits an Akamai edge co-located in Comcast's Philadelphia POP — RTT under 5 ms, no transit network involved. Without peering, the same request would traverse one or more transit providers, adding tens of milliseconds and incurring per-byte transit fees. Every major CDN has peering arrangements with every major ISP; that is much of what you pay for when you buy CDN service.
Peering disputes occasionally make news. When Netflix's bandwidth demand on Comcast exceeded the peering balance in 2014, Netflix had to pay for paid peering, and the dispute reached US regulators. Similar friction recurs around every dominant streaming service. By 2026 the largest streamers (Netflix, YouTube, Amazon Prime Video) operate their own CDN-equivalent infrastructure with deep peering across thousands of ISPs, bypassing third-party CDNs for most of their delivery.
