fact sheet what is an internet exchange point?

What is an Internet Exchange Point? with each other at exchange points to allow An Internet exchange point (IXP) is where their customers to communicate. More recently, Internet networks come together to peer or exchange point customers are often content exchange traffic between their networks. providers, who peer with ISPs to get their For more information on peering, please see content to the ISPs’ customers. Content the Netnod “What is peering?” document. providers also connect to exchange points to exchange traffic with other content providers, Internet exchange points are not Internet including advertising networks interconnecting service providers. While they allow network with advertiser-supported websites, email operators to exchange traffic with other network providers exchanging email messages, and operators, an exchange point will not sell you the like. anything resembling complete Internet connectivity. They are, instead, one of the building What is it, technically? blocks around which the Internet is built. An exchange point is usually an ethernet switch, much like the ethernet switches that Who connects to them? connect computers in an office network. Each Any network that wants to peer with other network connecting to the exchange point networks can connect to an exchange point. connects one or more of its routers to the Traditionally, this meant Internet service exchange point’s ethernet switch, and they providers (ISPs), who would sell Internet access send traffic across the ethernet switch to to their customers. They would interconnect routers belonging to other networks.

An Internet exchange point with four networks connected

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www.netnod.se 1 fact sheet What is an Internet Exchange Point?

Some exchange points use more complex large number of networks. Netnod takes a designs, connecting multiple ethernet switches different approach, keeping its exchange in multiple buildings, and sometimes using switches in underground telecom bunkers, other network protocols to carry traffic between and having networks connect to them via fibre those switches. Even in those cases, the hand- cables from other buildings. off to other networks is still done as an ethernet connection. However, in Stockholm, Netnod has expanded its exchange switch fabric with DWDM equip- Reseller models ment at the major data centres. Netnod has The larger exchange points offer so-called resel- also installed switch equipment at other sites ler models, where networks can connect to the in Stockholm, to make it easy for networks to exchange through a reseller who supplies the connect to the Netnod exchange from different connection and the port at the exchange point. locations. Netnod does this through the Netnod Reach partner program, which allows networks to Who operates exchange points? boost their international footprint and access Several different types of organisations operate the full range of Netnod’s unique routes in a exchange points. Some are operated by simple, and cost-effective way. organisations made up of the members who connect to the exchange. Others are operated Where are they? by commercial organisations, sometimes to Exchange points are usually in big telecom facilitate interconnections in buildings they buildings where the networks that connect own, and sometimes as tenants of colocation to them also have equipment. This makes it facilities just like the networks that connect simple to run the connections, but means that to them. a problem in a single building can damage a

An Internet exchange point with networks connected through a reseller model

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