Industry Solutions and Trends
Technology is more than just networking and Juniper experts share their views on all the trends affecting IT
Industry Solutions and Trends
Prediction from 2007 about core routers comes true early

In 2007, when we were about to launch our erstwhile flagship core/peering router, T1600, I showed this slide at various events:




As you can see, I predicted that by 2H 2016 or 2017, we would have a core router with 3000 Gbps (i.e. 3 Tbps) capacity per slot. As it turned out, my prediction was a bit conservative as our PTX5000, with the new ExpressPlus linecards, already has exactly that capacity per slot!


Back in 2007, we didn’t know whether such a feat would be actually be possible, because visibility of the necessary enabling technologies only extended about five years into the future. But we did know that there would be many challenges, including:


  • ASIC throughput
  • memory capacity and i/o bandwidth
  • interconnect bandwidth between chips
  • power consumption and cooling

These have been overcome in the ExpressPlus linecards by incorporating single-ASIC Packet Forwarding Engines (PFEs) with Hybrid Memory Cube (HMC) memory.These PFEs are more compact and more power-efficient than the multi-ASIC PFEs with older memory technology used in previous-generation routers. As well as having higher throughput, the linecards are nowadays able to perform more functions. For example, jflow needed special Service PICs in the days of T1600 but is now supported directly on the linecards on PTX.


I suppose the obvious question is what to expect a further 8 or 9 years in the future? If we assume the same growth rate as over the last 8 or 9 years, that would imply a router with about 90 Tbps capacity per slot in 2023 or 2024. Like before, it’s difficult to know now whether this will be feasible, and much the same list of challenges still applies as back in 2007. Let’s see if this blog comes back to haunt me in 2023/24...