Very helpful observations, Matt, thank you.

How comfortably does the phrase "routed optical networks over Ethernet without ROADMs" sit with you?
I mean: would you accept a limitation of "optical network" to the case of
a network without optical layer switching (of the type done by add-drop multiplexers)?

Cheers,

Etienne

On Mon, May 1, 2023 at 10:57 PM Matt Erculiani <merculiani@gmail.com> wrote:
Hi Etienne

In short, the idea is that optical networks are wasteful and routers do a better job making more use of a network's capacity than ROADMs. Take the extra router hop (or 3 or 8) versus short-cutting it with an optical network because the silicon is so low-latency anyway that it hardly makes a difference now. Putting more GBs per second on fewer strands means saving a lot of money on infrastructure costs.

400G ZR comes to mind as a foundational technology since it basically made active optical muxponder equipment obsolete in the metro. The savings here means telcos/enterprises can afford more router ports, which we've already established can utilize paths more efficiently anyway. Otherwise, this is more of a concept and can be executed with a variety of pre-existing technologies, or someone's new secret sauce that bakes everything together like SD-WAN did to its constituent technologies.

-Matt


On Mon, May 1, 2023 at 12:30 PM Etienne-Victor Depasquale via NANOG <nanog@nanog.org> wrote:
Hello folks,

Simple question: does "routed optical networks" have a clear meaning in the metro area context, or not?

Put differently: does it call to mind a well-defined stack of technologies in the control and data planes of metro-area networks?

I'm asking because I'm having some thoughts about the clarity of this term, in the process of carrying out a qualitative survey of the results of the metro-area networks survey.

Cheers,

Etienne

--
Ing. Etienne-Victor Depasquale
Assistant Lecturer
Department of Communications & Computer Engineering
Faculty of Information & Communication Technology
University of Malta


--
Matt Erculiani
ERCUL-ARIN


--
Ing. Etienne-Victor Depasquale
Assistant Lecturer
Department of Communications & Computer Engineering
Faculty of Information & Communication Technology
University of Malta
Web. https://www.um.edu.mt/profile/etiennedepasquale