Internet peering is a connection between two IP networks that allow traffic to flow from sources in either of the networks to destinations in the other without allowing traffic to flow to destinations traversing the peer—or in other words, to travel via the internet.
Peering is configured using BGP (Border Gateway Protocol) which exchanges routing information between two systems, defined by their Autonomous System Numbers (ASNs). The configuration of BGP on both sides of the connection determines whether the connection is a “peering” or an “internet access/transit” type of connection.
Peering is an essential strategy for businesses that:
Network peering works by allowing devices on one network to send traffic directly to devices on another network. Peering provides more direct control over how you participate in the internet.
For example, a business might have an application hosted on-premises to download data from the public cloud. The application could access the data over the internet, the typical approach.
However, if the business sets up a peering connection between the on-premises location and the public cloud, data is downloaded directly without using the public internet. In other words, the data downloads without using third-party providers that do not provide the level of control needed.
Let’s take a little broader view for a moment, just to put internet peering in context. Peering is a type of interconnection, and generally, there are two types of interconnections:
Transit: The networks interconnect so that one (usually an ISP, telco, or carrier) can provide reachability to the entire Internet for the other, which is typically an “endpoint” entity (e.g., enterprise, content or application provider, residential broadband provider, etc.). In most cases, there is a commercial relationship. The endpoint entity pays the ISP to carry traffic to and from the Internet.
Peering: The networks interconnect to exchange only traffic that originates or terminates within their networks (or perhaps the networks of their direct customers). Peering is usually between—not surprisingly—peers, meaning entities that are comparable.
Historically, peering was established between networks that found a mutual benefit from the connection without payments between the parties.
For an IP network to peer, it needs an ASN (Autonomous System Number) and its own IP address space. Peering is then configured using BGP (Border Gateway Protocol) which exchanges routing information between the two ASNs. BGP is also used for internet access when businesses have an ASN and their own address space. The configuration of BGP on both sides of the connection determines whether it is a peering or internet access/transit connection.
BGP is used for the logical connection but needs a physical or virtual path between the two networks that connect. The most common approaches for this are:
By making it possible to avoid routing traffic over the internet, peering provides several significant advantages:
While peering provides many advantages, it’s not trivial to set up or manage. So, how do you decide if peering is the right choice for you and develop an understanding of potential peers and with whom to partner?
Kentik can help you find peering targets and understand the impact on connectivity. You can optimize cost and improve performance by peering more efficiently. Kentik enables you to evaluate potential peering partners, measure traffic ratios, and build data-driven business cases to support interconnection decisions.
Start a free trial to try it yourself.