What is PeeringDB?
PeeringDB is the public directory where networks document their peering details: which exchanges they are present at, their traffic levels, their peering policy, and who to contact. Before two networks set up a session, one side almost always checks the other's PeeringDB entry first.
It is also a practical research tool for anyone analyzing traffic. Look up an ASN in PeeringDB and you can see how connected the network is, where it exchanges traffic, and how large it claims to be. Pair that with an ASN lookup on any IP in your logs, and you go from a bare number to a real picture of the operator behind it.
How peering shapes the AS path you see
Every peering decision changes the routes BGP prefers. When two networks peer, traffic between them stops flowing through intermediate ASNs, so AS paths get shorter. When a peering relationship breaks, paths suddenly lengthen and shift through transit providers, which you can watch happen in a looking glass.
For most teams the takeaway is simpler: the ASN an IP belongs to tells you whose network decisions govern that traffic. Abstract's IP Intelligence API returns that ASN, the operator's name, and its type for any address, so the routing world's structure becomes a usable signal in your own product.
Frequently Asked Questions
What is BGP peering?
BGP peering is an agreement between two autonomous systems to connect directly and exchange each other's routes using BGP, usually without payment. It gives both networks shorter paths and lower transit costs.
What is the difference between peering and transit?
Peering exchanges only the two networks' own routes, typically for free. Transit is a paid service where a provider carries your traffic to the whole internet. Networks peer where they can and buy transit for the rest.
What is PeeringDB used for?
PeeringDB is the public directory of networks' peering information: exchange presence, traffic levels, policies, and contacts. Networks use it to evaluate and arrange peering; analysts use it to understand who a network is.
Do you need your own ASN to peer?
Yes. BGP sessions are established between autonomous systems, so each side needs its own ASN and its own address space to announce. How networks get one is covered in how ASNs are assigned.
Is peering always free?
No. Settlement-free peering is the norm between networks of similar size, but when the relationship is unbalanced the larger side may charge for the connection, an arrangement usually called paid peering.
