Re: Routed optical networks

[Dave Taht <dave.taht () gmail com>]

Up until this moment I was feeling that my take on the decline of traffic
growth was somewhat isolated, in that I have long felt that we are nearing
the top of the S curve of the data we humans can create and consume. About
the only source of future traffic growth I can think of comes from getting
more humans online, and that is a mere another doubling.

On the other hand, predictions such as 640k should be enough for everyone
did not pan out.

On the gripping hand, there has been an explosion of LLM stuff of late,
with enormous models being widely distributed in just the past month:

https://lwn.net/Articles/930939/

Could the AIs takeoff lead to a resumption of traffic growth? I still don´t
think so...


On Thu, May 4, 2023 at 10:59 PM Vasilenko Eduard via NANOG <nanog () nanog org>
wrote:

> Disclaimer: Metaverse has not changed Metro traffic yet. Then …
>
>
>
> I am puzzled when people talk about 400GE and Tbps in the Mero context.
>
> For historical reasons, Metro is still about 2*2*10GE (one “2” for
> redundancy, another “2” for capacity) in the majority of cases worldwide.
>
> How many BRASes serve more than 40000/1.5=27k users in the busy hour?
>
> It means that 50GE is the best interface now for the majority of cases.
> 2*50GE=100Gbps is good room for growth.
>
> Of course, exceptions could be. I know BRAS that handles 86k subscribers
> (do not recommend anybody to push the limits – it was so painful).
>
>
>
> We have just 2 eyes and look at video content about 22h per week (on
> average). Our eyes do not permit us to see resolution better than
> particular for chosen distance (4k for typical TV, HD for smartphones, and
> so on). Color depth 10bits is enough for the majority, 12bits is sure
> enough for everybody. 120 frames/sec is enough for everybody. It would
> never change – it is our genetics.
>
> Fortunately for Carriers, the traffic has a limit. You have probably seen
> that every year traffic growth % is decreasing. The Internet is stabilizing
> and approaching the plateau.
>
> How much growth is still awaiting us? 1.5? 1.4? It needs separate
> research. The result would be tailored for whom would pay for the research.
>
> IMHO: It is not mandatory that 100GE would become massive in the metro. (I
> know that 100GE is already massive in the DC CLOS)
>
>
>
> Additionally, who would pay for this traffic growth? It also limits
> traffic at some point.
>
> I hope it would happen after we would get our 22h/4k/12bit/120hz.
>
>
>
> Now, you could argue that Metaverse would jump and multiply traffic by an
> additional 2x or 3x. Then 400GE may be needed.
>
> Sorry, but it is speculation yet. It is not a trend like the current
> (declining) traffic growth.
>
>
>
> Ed/
>
> *From:* NANOG [mailto:nanog-bounces+vasilenko.eduard=huawei.com () nanog org]
> *On Behalf Of *Phil Bedard
> *Sent:* Thursday, May 4, 2023 8:32 PM
> *To:* Etienne-Victor Depasquale <edepa () ieee org>; NANOG <nanog () nanog org>
> *Subject:* Re: Routed optical networks
>
>
>
> It’s not necessarily metro specific although the metro networks could lend
> themselves to overall optimizations.
>
>
>
> The adoption of ZR/ZR+ IPoWDM currently somewhat corresponds with your
> adoption of 400G since today they require a QDD port.   There are 100G QDD
> ports but that’s not all that popular yet.   Of course there is work to do
> something similar in QSFP28 if the power can be reduced to what is
> supported by an existing QSFP28 port in most devices.   In larger networks
> with higher speed requirements and moving to 400G with QDD, using the DCO
> optics for connecting routers is kind of a no-brainer vs. a traditional
> muxponder.   Whether that’s over a ROADM based optical network or not,
> especially at metro/regional distances.
>
>
>
> There are very large deployments of IPoDWDM over passive DWDM or dark
> fiber for access and aggregation networks where the aggregate required
> bandwidth doesn’t exceed the capabilities of those optics.  It’s been done
> at 10G for many years.  With the advent of pluggable EDFA amplifiers, you
> can even build links up to 120km* (perfect dark fiber)  carrying tens of
> terabits of traffic without any additional active optical equipment.
>
>
>
> It’s my personal opinion we aren’t to the days yet of where we can simply
> build an all packet network with no photonic switching that carries all
> services, but eventually (random # of years) it gets there for many
> networks.  There are also always going to be high performance applications
> for transponders where pluggable optics aren’t a good fit.
>
>
>
> Carrying high speed private line/wavelength type services as well is a
> different topic than interconnecting IP devices.
>
>
>
> Thanks,
>
> Phil
>
>
>
>
>
> *From: *NANOG <nanog-bounces+bedard.phil=gmail.com () nanog org> on behalf
> of Etienne-Victor Depasquale via NANOG <nanog () nanog org>
> *Date: *Monday, May 1, 2023 at 2:30 PM
> *To: *NANOG <nanog () nanog org>
> *Subject: *Routed optical networks
>
> 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
>
> Web. https://www.um.edu.mt/profile/etiennedepasquale


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Dave Täht CSO, LibreQos