Contrary to popular belief, the Internet is not one massive sprawling network, but rather a collection of much smaller networks that connect via Peering Points and exchange information about the IP addresses (and hence customers) that they contain. In this way each network is able to build up a picture of the Internet and how to reach IP addresses that it itself does not own.
Each network is known as an Autonomous System (AS), although as providers have consolidated one Service Provider may contain several ASes. They use a protocol called Border Gateway Protocol (BGP) to communicate with each other and share routes.
Peering vs. Transit
Peering is distinct from Transit in that peers usually sign an agreement to share traffic between each other at an agreed rate without cost (except the cost of provisioning a circuit). Transit is a paid agreement, usually with a bigger carrier, for them to provide the smaller network with access to Internet routes that they cannot reach. Most Service Providers will have a mix of both peering and transit agreements in place.
Different types of peering
The most common type of peering is Public Peering, whereby providers meet at an Internet exchange site. Here a range of switches are provided that each provider connects to. Once the cabling to the switch is done the providers enter into a formal peering agreement with each other at the site, but only one set of cables is needed. An example is London INternet eXchange (LINX).
Alternatively, providers will enter into a private peering arrangement with each other. This also usually happens in a colocation facility but here the two providers run cables directly between each other solely for the purpose of exchanging routes and traffic.
How can help?
Whilst providers must make their own peering agreements, they will require a highly scalable router with which to connect to Peering Points. These routers often require a very large control plane (that is able to receive and process multiple millions of routes) but not a huge forwarding plane (as the amount of traffic passed is not in direct correlation to the routes exchanged).
has 15 years’ experience of working with Juniper Networks, Nokia and Cisco to provide best of breed routing capabilities in small footprint and low power consumption models, helping providers to reduce the cost of Peering.