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New Optical Form Factors for 400 Gigabit Ethernet

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Re: New Optical Form Factors for 400 Gigabit Ethernet

#31

Post by Retric »

walrus01 wrote: post #3
bjoli wrote: post #2

Does aanyone here work with consuming (not just passing it kn) these amounts of traffic? How do you manage to get anything meaningful out of it?

network engineer here: nobody connects a 200 or 400GbE interface linecard off a router to a single anything... The purpose is for ISP-to-ISP interconnections for truly huge amounts of traffic. For example direct peering in the same IX/carrier hotel between a huge source of content (youtube/google, netflix, etc) and a huge ISP (comcast, centurylink). For a big ISP, also things like 100GbE connections from a city's pai…

Raw high frame rate video can into that range.

Phantom v2640 for example does 6600 frames per second at a at 2048 x 1952 resolution = 26 Gpx/sec or something like 100Gbit.

Currently they simply buffer everything on Camera and use 10GigE, but in theory they could look into 100+GbE connections for newer designs.

Re: New Optical Form Factors for 400 Gigabit Ethernet

#32

Post by agoodthrowaway »

walrus01 wrote: post #29
francoisLabonte wrote: post #24

The real debate is between OSPF and QSFP-DD as they are the only ones with a shot at high density. QSFP-DD is backwards compatible so that you can run your 400G port as a 100G or 40G with 4 lanes at 25G/10G. OSFP will be able to do the same thing but with an adapter from OSFP to QSFP But what this article fails to mention is that OSFP is the connector of the future that will support 8 lanes of 100G to support 800G et…

I am also optimistic about OSFP as compared to the QSFP size for 400G. I'm not a laser engineer but I do have a pretty good understanding of how 400G will be achieved through two strands of singlemode. For medium reach optics it's actually an 8-channel CWDM with prism built into each optic, so the optic body needs to be large enough to dissipate the heat from eight separate 25 Gbps lasers. CFP size will obviously han…

100G/wave device will be the norm moving forward and 8 lane devices for 400G won’t be around much except in niche applications.

Re: New Optical Form Factors for 400 Gigabit Ethernet

#33

Post by walrus01 »

Retric wrote: post #31
walrus01 wrote: post #3

Earlier quoted context omitted.

network engineer here: nobody connects a 200 or 400GbE interface linecard off a router to a single anything... The purpose is for ISP-to-ISP interconnections for truly huge amounts of traffic. For example direct peering in the same IX/carrier hotel between a huge source of content (youtube/google, netflix, etc) and a huge ISP (comcast, centurylink). For a big ISP, also things like 100GbE connections from a city's pai…

Raw high frame rate video can into that range. Phantom v2640 for example does 6600 frames per second at a at 2048 x 1952 resolution = 26 Gpx/sec or something like 100Gbit. Currently they simply buffer everything on Camera and use 10GigE, but in theory they could look into 100+GbE connections for newer designs.

upcoming on-camera flash memory interface

https://en.wikipedia.org/wiki/CFexpress

basically a way of putting a M.2 interface NVME PCI-Express SSD into a camera.

https://petapixel.com/2018/04/09/prograde-digital-unveils-wo...

Re: New Optical Form Factors for 400 Gigabit Ethernet

#34

Post by hinkley »

SteveNuts wrote: post #19
hinkley wrote: post #12

Earlier quoted context omitted.

Can’t you saturate 100GB easily with a single disk array these days?

Yes, I've worked with several that can do that. The interesting thing with disk arrays now is the controller heads are becoming the bottleneck. You used to have many many shelves of SAS drives per controller pair, now the SSDs are so fast that the CPUs are saturated and you have to scale out, not up.

If I can't (reliably) handle 100GBps coming from the RAID array it sounds like I'm not going to be able to handle 400GBps coming in from the NIC.

So these really are just for interconnects for the time being, until server hardware gets faster.

Re: New Optical Form Factors for 400 Gigabit Ethernet

#35

Post by marzell »

gsich wrote: post #27
hesdeadjim wrote: post #7

I remember having to schedule a 780Kb download overnight and hoping no one picked the phone up. Or years later having to download shows in advance (illegally because they weren’t available) because streaming wasn’t possible. Now I casually (and legally) boot up any show I feel like within seconds at HD resolutions. I love thinking about the sheer amount of data that is traversing around the internet now. And it’s mor…

Bandwidth is not the issue in PUBG.

Yeah exactly... while higher bandwidth may open the door for some new things in games... I think it's possible there is not a single game out there that really needs even as much bandwidth as a single HD video stream. The limiting factor is really latency and jitter.

Re: New Optical Form Factors for 400 Gigabit Ethernet

#36

Post by walrus01 »

agoodthrowaway wrote: post #32
walrus01 wrote: post #29

Earlier quoted context omitted.

I am also optimistic about OSFP as compared to the QSFP size for 400G. I'm not a laser engineer but I do have a pretty good understanding of how 400G will be achieved through two strands of singlemode. For medium reach optics it's actually an 8-channel CWDM with prism built into each optic, so the optic body needs to be large enough to dissipate the heat from eight separate 25 Gbps lasers. CFP size will obviously han…

100G/wave device will be the norm moving forward and 8 lane devices for 400G won’t be around much except in niche applications.

for long reach, yes, but not for ISP-to-ISP interconnection... the cost of coherent (QPSK, 8PSK, 16QAM) 100G SerDes and modulation/demodulation is considerably higher and only justified if going a great many km. For intra-peering-facility connections I don't see coherent 100G (or multiples of coherent 100G bundled by CWDM into 200G, 400G interfaces) becoming the norm anytime soon.

Re: New Optical Form Factors for 400 Gigabit Ethernet

#37

Post by thathappened »

Klinky wrote: post #8
hesdeadjim wrote: post #7

I remember having to schedule a 780Kb download overnight and hoping no one picked the phone up. Or years later having to download shows in advance (illegally because they weren’t available) because streaming wasn’t possible. Now I casually (and legally) boot up any show I feel like within seconds at HD resolutions. I love thinking about the sheer amount of data that is traversing around the internet now. And it’s mor…

Multiplayer gaming has more issues with latency than a lack of raw bandwidth.

Latency is usually from bandwidth being queued somewhere along the path

Re: New Optical Form Factors for 400 Gigabit Ethernet

#38

Post by Retric »

walrus01 wrote: post #33
Retric wrote: post #31

Earlier quoted context omitted.

Raw high frame rate video can into that range. Phantom v2640 for example does 6600 frames per second at a at 2048 x 1952 resolution = 26 Gpx/sec or something like 100Gbit. Currently they simply buffer everything on Camera and use 10GigE, but in theory they could look into 100+GbE connections for newer designs.

upcoming on-camera flash memory interface https://en.wikipedia.org/wiki/CFexpress basically a way of putting a M.2 interface NVME PCI-Express SSD into a camera. https://petapixel.com/2018/04/09/prograde-digital-unveils-wo...

According to the link that's currently limited to 2 GB/s which far to slow to use for this. Phantom v2640 needs ~50+x that speed to do it in real time and I assume the bandwidth needs will keep increasing on the next model.

Re: New Optical Form Factors for 400 Gigabit Ethernet

#39

Post by fulafel »

bjoli wrote: post #2

Does aanyone here work with consuming (not just passing it kn) these amounts of traffic? How do you manage to get anything meaningful out of it?

5G base stations cite 50 Gbps bandwidth, connect a bunch of these together in an urban area and you might want 400G for their uplink/backbone/whatever it's called.

Re: New Optical Form Factors for 400 Gigabit Ethernet

#40

Post by djrogers »

francoisLabonte wrote: post #24

The real debate is between OSPF and QSFP-DD as they are the only ones with a shot at high density. QSFP-DD is backwards compatible so that you can run your 400G port as a 100G or 40G with 4 lanes at 25G/10G. OSFP will be able to do the same thing but with an adapter from OSFP to QSFP But what this article fails to mention is that OSFP is the connector of the future that will support 8 lanes of 100G to support 800G et…

I get the attraction of OSFP, but in early days backward compatibility usually trumps future potential. If I'm buying an high density switch/router tomorrow (figuratively speaking), I'd greatly prefer the flexibility to use the density it provides for some existing lower speed connections. As long as QSFP-DD 'works', as a customer I'm not really concerned with which technology is more elegant or technically 'better'.

The problem this presents for OSFP going forward is that it encourages early adoption to steer toward QSFP-DD, which will tend to drive follow-on purchase decisions as well.

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