Summary

  • James Rice’s RIPE 93 proposal would give exchange ports routed Layer 3 connections in place of the shared Layer 2 peering LAN. The promised prize was cleaner forwarding and shorter paths.
  • Wolfgang Tremmel warned that moving control to the exchange could open a can of worms. His question turns a neat network diagram into a discussion about who chooses routes and who answers when they go wrong.

The Internet exchange has spent decades playing host: bring your router, meet other networks, decide whom to peer with. At a RIPE 93 BoF in Sofia on 26 October, James Rice proposed a different floor plan. Each participant’s port would become a point-to-point link to exchange routers. The shared Layer 2 broadcast domain and its route-server arrangement would give way to forwarding at Layer 3. Rice’s pitch promised correct forwarding, shorter paths and features familiar from transit.

It is the kind of diagram that makes an engineer reach for a marker. Wolfgang Tremmel reached for the question behind the marker. According to RIPE NCC’s meeting account, Gert Döring noted that the Layer 2 model leaves control with participants. Tremmel cautioned that handing control to the Layer 3 exchange could “open a can of worms.” The room’s reaction leaned cautious. No vote settled the architecture that evening.

Tremmel has earned the right to ask awkward routing questions. The RIPE biography traces him from network engineering at Xlink in 1994 through ISP operations and peering management, then a decade leading customer support at DE-CIX. Since 2016 he has headed its Academy, teaching customers BGP and routing protocols; he also chairs the RIPE IPv6 Working Group with two colleagues. A person who teaches route decisions for a living knows that the pleasant word automation rarely tells you who holds the override.

Rice’s case deserves engineering attention. So does the location of the steering wheel. A routed exchange would have to make its policy boundaries visible to members: which routes it accepts, which it forwards, how disputes are handled, and what happens when the exchange’s own control system misbehaves. Tremmel put that question on the table before anyone could mistake a cleaner cabling drawing for a settled operating bargain.