Facebook - In terms of hard, physical constraints, we considered factors such as:
Power: The power in a region is a fixed resource. Many of our regions already have dedicated power facilities with more than 100 MW of capacity. Just because we have the real estate to double the number of buildings, however, doesn’t mean we can double the available power for everything in those new buildings. On top of that, the higher bandwidth ASICs and optics (e.g., 400G) require more power. Therefore, the network would have used a disproportionate amount of the overall DC power budget.
Optics availability: The need for new data center buildings meant that whatever optics technology we selected had to be rolled out at a massive scale — and in time for our deployment goals. We had concerns about the availability of 400G optics at scale and the risk of adopting such leading-edge technology in these early stages.
In addition, we’ve learned that operating a data center fleet at Facebook’s scale means constantly evolving our networks. While we continue to roll out “green field” data centers, every iteration marks the “new” data centers as the ones we need to upgrade. This upgrade process is something we wanted to pay much more attention to in these future designs.
Optics
In order to leverage the mature 100G CWDM4-OCP optics, Minipack uses reverse gearboxes. The Broadcom TH3 switch ASIC has 256 lanes of 50G PAM4 SerDes to achieve 12.8T switching bandwidth, whereas the existing 100G CWDM4 optics come with four lanes of 25G NRZ SerDes. We use reverse gearbox chips in between to bridge the gap. There are a total of 32 reverse gearbox chips in Minipack (128x100G configuration), and each processes 4x100G ports.
https://engineering.fb.com/data-center-engine...-minipack/
Ok, check and double check, Facebook is building Power Plants because of its crazy high power usage, LWLG technology is already HALF the POWER of all the competition, and when it finalizes the 1V "Driverless" it will be about 20% or even less than that of all the competition, also you can see that Facebook is still working with 25Gb standalone transmissions enhanced with a complex modulation PAM4 which also adds an expensive factor to operate, LWLG is already on final optimizations of 100Gbs at 1V "driverless" which is FOUR TIMES THE SPEED and LWLG has plenty of headroom to go even faster with proven femtosecond response times!
Power: The power in a region is a fixed resource. Many of our regions already have dedicated power facilities with more than 100 MW of capacity. Just because we have the real estate to double the number of buildings, however, doesn’t mean we can double the available power for everything in those new buildings. On top of that, the higher bandwidth ASICs and optics (e.g., 400G) require more power. Therefore, the network would have used a disproportionate amount of the overall DC power budget.
Optics availability: The need for new data center buildings meant that whatever optics technology we selected had to be rolled out at a massive scale — and in time for our deployment goals. We had concerns about the availability of 400G optics at scale and the risk of adopting such leading-edge technology in these early stages.
In addition, we’ve learned that operating a data center fleet at Facebook’s scale means constantly evolving our networks. While we continue to roll out “green field” data centers, every iteration marks the “new” data centers as the ones we need to upgrade. This upgrade process is something we wanted to pay much more attention to in these future designs.
Optics
In order to leverage the mature 100G CWDM4-OCP optics, Minipack uses reverse gearboxes. The Broadcom TH3 switch ASIC has 256 lanes of 50G PAM4 SerDes to achieve 12.8T switching bandwidth, whereas the existing 100G CWDM4 optics come with four lanes of 25G NRZ SerDes. We use reverse gearbox chips in between to bridge the gap. There are a total of 32 reverse gearbox chips in Minipack (128x100G configuration), and each processes 4x100G ports.
https://engineering.fb.com/data-center-engine...-minipack/
Ok, check and double check, Facebook is building Power Plants because of its crazy high power usage, LWLG technology is already HALF the POWER of all the competition, and when it finalizes the 1V "Driverless" it will be about 20% or even less than that of all the competition, also you can see that Facebook is still working with 25Gb standalone transmissions enhanced with a complex modulation PAM4 which also adds an expensive factor to operate, LWLG is already on final optimizations of 100Gbs at 1V "driverless" which is FOUR TIMES THE SPEED and LWLG has plenty of headroom to go even faster with proven femtosecond response times!
