{"id":275,"date":"2018-01-08T12:12:21","date_gmt":"2018-01-08T17:12:21","guid":{"rendered":"https:\/\/itp.nyu.edu\/networks\/?page_id=275"},"modified":"2018-01-08T12:12:21","modified_gmt":"2018-01-08T17:12:21","slug":"network-connections-and-colocation-facilities","status":"publish","type":"page","link":"https:\/\/itp.nyu.edu\/networks\/explanations\/network-connections-and-colocation-facilities\/","title":{"rendered":"Network Connections and Colocation Facilities"},"content":{"rendered":"

I\u2019m sitting in Room 50 on the fourth floor of 721 Broadway, connected to the NYU wifi. I enter<\/span> www.anotheridea.co<\/span><\/a> in my browser and think \u201cOh no, I\u2019m late on another blog post.\u201d But then I wonder, \u201cHow did my website content get to being on my screen? Where does it live? Does it even live somewhere? Maybe I should write that blog post\u2026\u201d<\/span><\/p>\n

Connecting to a Network, ISPs and IXps<\/b><\/p>\n

In connecting to a network, there are consumers and content providers. Consumers request data\u2014email, the news, Netflix, etc\u2014 and content providers serve up the requested data.<\/span><\/p>\n

I, as a consumer, connect to the Internet from various networks \u2014 perhaps on my local network at home, at the neighborhood coffee shop or the ITP floor. My network connection to the Internet is facilitated by an Internet Service Provider (ISP) which owns cables and sells access to a network. And similarly, content providers also access the Internet through an ISP. <\/span>Some of the largest ISPs are Comcast, AT&T, Time Warner and Verizon.<\/span><\/p>\n

Consumers, content providers, and all the data in-between, access the Internet from many different networks. As such, these different networks need to connect to each other for data to be transmitted efficiently \u2014 that connection happens at particular points in space using particular protocols. <\/span><\/p>\n

Major networks connect through Internet Exchange Points<\/b><\/p>\n

At <\/span>Internet Exchange Points<\/span><\/a> (IXPs), three or more autonomous network systems connect and directly exchange traffic, rather than routing through third-party networks. IXPs are company-owned physical network access points, providing access to a <\/span>patch panel<\/span><\/i> which connects to other networks. They might own their buildings, or just patch panels in other buildings\u2014such as in a third-party colocation facility.<\/span><\/p>\n

IXP participants are commonly Internet Service Providers but may also include common carriers, content distributors (i.e. Netflix), hosting providers (i.e. Bluehost), or research and\/or education networks (i.e. New York University), among other classifications. Common carriers transport goods–such as data or internet access–for hire as a business to any customer willing to pay and must provide the same level of service to all potential customers indiscriminately. ISPs are considered common carriers.<\/span><\/p>\n

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IXPs partner with interconnection facilities and install access switches there. Networks that share an access switch can exchange traffic locally, otherwise it\u2019s routed through the patch panel at the IXP. Diagram based on Figure 1 in Giotsas, et al. \u201cMapping Peering Interconnections to a Facility\u201d.<\/figcaption><\/figure>\n

Colocation and Interconnection Facilities<\/b><\/p>\n

Broadly, any space in which different networks connect can be called an \u201cinterconnection facility\u201d. An interconnection facility is a particular physical location–be it an entire building or part of one–that offers secure space for networks to locate and operate equipment–routers, end devices, access switch–for making connections between other networks.<\/span> Co-locating network equipment makes data transfer across networks more efficient. Colocation might describe locating one\u2019s server near an ISP’s endpoint, or it might describe locating one\u2019s routers near an ISP or IXP location to maximize the connections to other networks.<\/span><\/p>\n

Such facilities can be distinguished across a number of aspects:<\/span><\/p>\n