On 5/12/24 20:35, Dave Cohen wrote:
It’s one of those things that makes a lot more sense on paper than in practice.
Not anymore. The majority of SDM subsea cables built with uncompensated fibre are using managed spectrum and spectrum sharing as viable business models for a not-so-insignificant population of their customer base.
I’ve found it to be operationally difficult from the perspective the provider and the user, primarily but not solely because any “co-managed” system is going to lend itself to finger pointing when issues arise.
And there is a case to be made for that concern. However, if you are in a position to be able to sell spectrum, it is very likely you are going to be implementing a vendor of note. Since that is most likely to be the case, those vendors have spectrum controllers that make this a viable business model, albeit at a $$ premium. This is not the type of service small DWDM operators using new-age DWDM vendors would typically be looking to sell. Such operators have to deal with keeping the lights on, never mind esoteric services like spectrum.
Even if it makes more commercial sense at first blush to prefer a spectrum solution over dark or traditional waves, I suspect that factoring in “labor cost wasted over unproductive troubleshooting” changes the equation a bit.
Alien wave and spectrum services attract a very high income, mainly through a capex-based upfront cost (IRU) that can be attractive to the host network. At those levels, providing their vendor has decent support for spectrum services, the revenue gain more-than makes up for all the logistical admin.
I also suspect that continued price compression on optical hardware will lead to fewer and fewer situations where it might make commercial sense at first blush too.
Well, legacy DWDM vendors will continue to charge a premium even for what is now standard electrical bandwidth services. Why? Because they still have all that legacy stuff to support, all their R&D to recoup, and because the bulk of their customers are no longer the telco, but content folk. New-age DWDM vendors are focused on coherent optical networks, which are primarily 100G and 400G. Why? Because that is where MSA and OpenROADM are currently at re: commercial availability. The legacy vendors will develop proprietary coherent pluggables that will support funky things such as 800G, 1.2T and 1.6T, but those won't be industry standard for some time (800G is getting there, though). What all this means is that if you are a legacy operator that is careful about spending money on newer DWDM technologies, a spectrum service from a larger carrier is going to be more attractive than ripping out your entire line system just so you can get from 10G or 40G to 400G. Of course, if you are a monopoly and have no alternatives to lean on, this doesn't count.
YMMV of course and there may be reasons beyond simple commercial models where spectrum might make sense for you, but I’d urge you to only consider it doing with a provider where you’ve had a track record of operational success working with them.
New-age DWDM vendors are not the workhorse of most of the large DWDM operator networks out there. That means that any operator of note you are likely to run into is going to be a Ciena, Infinera, Nokia, Adva, e.t.c., house, or something along those lines. Those vendors have reasonable spectrum-based solutions that smaller DWDM operators or ISP's would be willing to spend money on to avoid having to upgrade or deploy an entire line system. The reason that is feasible is because those larger operators are running vendors who push beyond what the MSA and OpenROADM groups are prescribing. You can already get coherent 100G and 400G channels on new-age DWDM vendors... that is not rocket science anymore. Of course, there is always the IPoDWDM question... but if I'm honest, I am still as unconvinced now in 2024 as I was back in 2008 that optical and IP folk would have a meeting of the minds on this. Mark.