Voice Peering: Why Isn’t It as Easy as IP Peering?

Coming from an IP engineering background and now working in telecoms at Localphone.com, I’ve learned there’s a surprising amount of crossover between the two worlds. After all, intercompany telecoms interconnections are increasingly happening over IP. But here’s the catch: what works in IP peering doesn’t neatly map onto the voice world.

I recently attended a PulverMedia conference on voice peering. I went in with some strong assumptions about what voice peering would involve—and promptly had them dismantled. One of the most enlightening moments came from Gary Kim, who said, “I’m more confused about where peering is going today than I was two years ago.” After a few days of presentations and good conversations, I relate.

Why Isn’t Voice Peering Like BGP?

My frustration: “Why can’t I configure a voice peer the way I configure a BGP peer?”

In IP peering, everything is gloriously standardised. Protocols are well-known, prefixes adhere to global norms, peering is usually settlement-free, and billing is straightforward because traffic is treated equally. In the voice world, it’s like stepping into a labyrinth where every turn introduces new quirks:

• Prefixes behave differently. Telephone numbers don’t follow the same elegant simplicity as IP prefixes.
• Protocols are inconsistent. Different companies use different media codecs, call signalling methods, and DTMF standards.
• Voice settlement is rarely free. Thanks to regulators and the long, messy history of commercial telephony, there’s almost always a cost involved.

Enter the Clearing House

This complexity has given rise to a familiar telecoms creature: the clearing house. These organisations act as intermediaries, translating codecs, signalling, and call detail records (CDRs) between peers. They provide a useful service, but it comes at a cost—literally and metaphorically. Clearing houses create barriers to entry, as they rarely offer their services for free. And for telcos that like to retain control of their networks, the model can feel intrusive.

Clearing houses abstract vital aspects of the call:

• Media abstraction risks lower call quality, leaving service providers blind to the route a call takes.
• Signalling abstraction can mangle error messages, making troubleshooting a nightmare.

There’s also the monopoly problem. If you belong to one clearing house and your potential peer belongs to another, you’re stuck. Some clearing houses have suggested protocols to allow them to peer with each other, but that only adds another layer of abstraction. For many service providers, this is a step too far.

Why Peer at All?

So, if voice peering is this complicated, why bother? Simple: it benefits everyone—telcos and customers alike.

• Bypass incumbents. Peering reduces reliance on national incumbents, cutting costs and improving quality.
• Better quality calls. IP-to-IP calls can eliminate legacy TDM legs, enabling clearer, wideband audio codecs.
• Cheaper rates. Direct peering between competitive telcos typically beats incumbent pricing.

In short, peering is a key strategy for next-gen telcos looking to deliver cheaper, higher-quality calls. The challenge lies in making it work without unnecessary intermediaries.

A Better Way Forward

The solution, I believe, is bilateral communication between telcos. Prefixes (phone numbers) and standards should be exchanged directly, without a clearing house acting as referee. To this end, I’m collaborating with some of the people I met at the conference to develop a new protocol. Think of it as TRIP 2.0, but with enough commercial logic baked in to make it genuinely useful.

I hope we publish an Internet-Draft this year. It’s an ambitious project, but one that could simplify voice peering and bring the world of telecoms a little closer to the elegance of BGP. Stay tuned—this is a work in progress, but it’s one I’m excited to share.

Post Script [2025]

We never got there and nothing in this field has changed (for the better).