How to Peer at an Internet Exchange: A Practical Guide

If you have ever wondered how to peer at an internet exchange, the latest consolidation in Europe is a timely nudge. NL-ix’s acquisition of Sweden’s STHIX shows that exchange operators are building bigger, better-connected footprints, and that makes joining one more valuable for anyone running a network, a hosting platform or a connected-device service.

Peering means swapping traffic directly with other networks instead of paying a transit provider to carry it. Done well, it cuts latency, trims transit bills and gives you more control over routing. Here is a practical, step-by-step path for a small or mid-sized network.

What You Need Before You Start

Before you contact any exchange, make sure you have the following. An Autonomous System Number (ASN) and at least one IP prefix, both obtained from your regional registry (for Europe, that is RIPE NCC, usually through a local internet registry or sponsoring LIR). A router capable of running BGP, ideally with enough memory for full tables if you also buy transit. A presence at, or a way to reach, a data center where the exchange has a point of presence, either with your own cage or through a remote peering reseller. And a PeeringDB record, which is effectively your public networking business card.

You also need some baseline knowledge of BGP: sessions, prefixes, AS paths and filters. If your team is new to it, practise in a lab with software routers like BIRD or FRRouting before touching production.

Step 1: Choose the Right Exchange and Connection Type

Start by looking at where your traffic actually goes. Pull NetFlow or sFlow data for a few weeks and list your top destination networks: content providers, cloud platforms, CDNs, eyeball ISPs. Then check PeeringDB to see which exchanges those networks use. The best exchange for you is the one where most of your heavy destinations already are.

Compare a few practical factors. Participant count and traffic volume tell you how much value you will get. Port speeds and pricing vary, with many exchanges offering 1G and 10G ports at predictable monthly fees. Location matters too: a Nordic exchange makes sense if your users are in Scandinavia, while a Dutch or German hub gives broader European reach. Check whether the exchange offers route servers, which let you reach many peers with a single BGP session, and whether it publishes clear technical and security requirements.

Then choose how to connect. If you already have equipment in a facility where the exchange is present, order a cross-connect and a physical port. If you do not, remote peering through a partner can get you started without a rack. It costs more per megabit over time, but it is a fine way to test the benefits before committing to hardware.

Step 2: Prepare Your Network and Apply for a Port

Get your house in order first. Create route objects for your prefixes in the IRR database and publish RPKI ROAs, so other networks can validate that you are allowed to announce them. Many exchanges and large peers now filter on RPKI status, and invalid routes get dropped. Set up your PeeringDB entry with accurate contact details, traffic estimates and peering policy.

Then apply to the exchange. You will typically submit an order form with your ASN, contact information and port choice, and sign an agreement. After approval, you receive a peering LAN address (IPv4 and IPv6) for your port, plus details of the route servers. Plan the maintenance window and tell your upstream team, since your routing table is about to grow.

Write your routing policy before you configure anything. Decide what you will announce (only your own prefixes and those of your customers), what you will accept (valid, expected prefixes from each peer) and what you will never accept (bogons, your own space, overly long paths, default routes). A written policy prevents mistakes at 2 a.m.

Step 3: Configure BGP Sessions and Verify

With the port live, configure your router’s interface using the assigned addresses. Then set up BGP sessions with the route servers first. That gives you instant reach to many networks with minimal effort. Apply prefix limits, max-AS-path limits and strict import and export filters on every session. Following the MANRS guidelines is a solid reference for routing security.

After the route servers are stable, add bilateral sessions with the networks that carry most of your traffic. Contact their peering teams using the details in PeeringDB, share your ASN and the IP you use on the exchange LAN, and agree on any specifics. Large content networks often have automated request systems, so a short, polite message with your traffic estimate goes a long way.

Finally, verify and monitor. Check that routes are being received and best-path selection prefers the peering path over transit where you intend it to. Confirm with traceroutes and latency tests to key destinations. Watch your interface graphs, session states and prefix counts, and set alerts for session drops or sudden prefix spikes. Review traffic shifts after a month, then adjust your transit commit downward if the numbers justify it.

For IoT and connected-device operators, this matters directly. Lower latency and more predictable routing improve device telemetry, firmware delivery and remote control, particularly as more services depend on stable regional connectivity.

Common Mistakes to Avoid

Skipping route filtering. An accidental leak can send traffic from half the internet through your small router. Always filter inbound and outbound, and use prefix limits.

Choosing an exchange by name alone. A famous exchange with none of your destination networks gives you little. Let your traffic data decide.

Treating peering as set and forget. Peers change, ports saturate and policies evolve. Review utilisation quarterly and upgrade ports before they hit 70% to 80%.

Key Takeaways

• Start with data: Your own traffic reports tell you which exchange will pay off.
• Prepare the paperwork: ASN, IRR objects, RPKI ROAs and PeeringDB make approval and trust easier.
• Use route servers first: Broad reach with little effort, then add bilateral sessions for the big flows.
• Filter strictly: Prefix limits and validation protect you and everyone else on the LAN.
• Monitor and review: Peering is an ongoing practice, not a one-off project.

Need Expert Help?

If this feels like a lot to manage alone, TecniForge can handle the heavy lifting. Our team specializes in custom software development and AI integration. Get in touch with our experts.

Also read: The NL-ix and STHIX Internet Exchange Deal Explained, our earlier coverage on why this matters today.

Your challenge: export a week of flow data this Friday and list your top ten destination networks. That list is the start of your peering plan.