Internet Exchange Point (IXP)
A physical location where multiple networks connect to exchange traffic via peering. IXPs reduce the need for transit and lower latency between peered networks. Major IXPs handle terabits of traffic per second.
Full Explanation
An Internet Exchange Point (IXP) is a physical location, usually inside a data center, where multiple networks connect to exchange traffic directly with each other. Instead of paying a transit provider to carry traffic between two networks, those networks can peer at an IXP and hand traffic off directly. This reduces latency because packets take a shorter path, and it reduces cost because peering is typically settlement-free (both sides agree to exchange traffic without payment).
Major IXPs handle enormous amounts of traffic. DE-CIX Frankfurt regularly peaks above 10 Tbps and connects over 1,000 networks. AMS-IX in Amsterdam, LINX in London, and Equinix IX locations worldwide are other major hubs. These IXPs form the physical backbone of internet interconnection.
CDNs love IXPs. By colocating cache servers directly inside IXP facilities, a CDN can peer with dozens or hundreds of ISPs at a single location. When a user on a local ISP requests content, the traffic goes from the ISP directly to the CDN's server in the same building, never touching the wider internet. This is why CDN PoPs are so often physically inside IXP data centers.
The difference is measurable. Traffic going through a transit provider might add 10-30ms of latency and cost money per gigabit. Traffic exchanged at an IXP between peered networks adds maybe 1-2ms and costs only the port fee. For a CDN serving petabytes per day, the cost savings and performance gains from IXP peering are massive.
Examples
Some of the largest IXPs by peak traffic (as of recent data):
IXP Location Peak Traffic Connected Networks
DE-CIX Frankfurt Frankfurt, DE ~14 Tbps 1000+
AMS-IX Amsterdam, NL ~12 Tbps 900+
LINX London, UK ~8 Tbps 950+
Equinix IX Ashburn Ashburn, US ~5 Tbps 300+
NAPAfrica (IX) Johannesburg, ZA ~2 Tbps 500+You can see which networks peer at a given IXP using PeeringDB:
# Query PeeringDB API for networks at DE-CIX Frankfurt (IX ID 31)
curl -s "https://www.peeringdb.com/api/netixlan?ixlan_id=31" | python3 -m json.tool | head -50Video Explanation
Frequently Asked Questions
A physical location where multiple networks connect to exchange traffic via peering. IXPs reduce the need for transit and lower latency between peered networks. Major IXPs handle terabits of traffic per second.
Some of the largest IXPs by peak traffic (as of recent data):
IXP Location Peak Traffic Connected Networks
DE-CIX Frankfurt Frankfurt, DE ~14 Tbps 1000+
AMS-IX Amsterdam, NL ~12 Tbps 900+
LINX London, UK ~8 Tbps 950+
Equinix IX Ashburn Ashburn, US ~5 Tbps 300+
NAPAfrica (IX) Johannesburg, ZA ~2 Tbps 500+You can see which networks peer at a given IXP using PeeringDB:
# Query PeeringDB API for networks at DE-CIX Frankfurt (IX ID 31)
curl -s "https://www.peeringdb.com/api/netixlan?ixlan_id=31" | python3 -m json.tool | head -50Related CDN concepts include:
- Peering — Direct network interconnection between two autonomous systems, bypassing transit providers. Reduces latency and cost. CDNs …