Re: [Cerowrt-devel] [Bloat] DC behaviors today

[dpreed@reed.com]

[-- Attachment #1: Type: text/plain, Size: 2940 bytes --]


I suggest we stop talking about throughput, which has been the mistaken idea about networking for 30-40 years.
 
Almost all networking ends up being about end-to-end response time in a multiplexed system.
 
Or put another way: "It's the Latency, Stupid".
 
I get (and have come to expect) 27 msec. RTT's under significant load, from Boston suburb to Sunnyvale, CA.
 
I get 2 microsecond RTT's within my house (using 10 GigE).
 
What will we expect tomorrow?
 
This is related to Bufferbloat, because queueing delay is just not a good thing in these contexts - contexts where Latency Matters. We provision multiplexed networks based on "peak capacity" never being reached.
 
Consequently, 1 Gig to the home is "table stakes". And in DOCSIS 3.1 deployments that is what is being delivered, cheap, today.
 
And 10 Gig within the home is becoming "table stakes", especially for applications that need quick response to human interaction.
 
1 NvME drive already delivers around 11 Gb/sec at its interface. That's what is needed in the network to "impedance match".
 
802.11ax already gives around 10 Gb/sec. wireless (and will be on the market soon).
 
The folks who think that having 1 Gb/sec to the home would only be important if you had to transfer at that rate 8 hours a day are just not thinking clearly about what "responsiveness" means.
 
For a different angle on this, think about what the desirable "channel change time" is if a company like Netflix were covering all the football (I mean US's soccer) games in the world. You'd like to fill the "buffer" in 100 msec. so channel change to some new channel is responsive. 100 msec. of 4K sports, which you are watching in "real time" needs to be buffered, and you want no more than a second or two of delay from camera to your screen. So buffering up 1 second of a newly selected 4 K video stream in 100 msec. on demand is why you need such speeds. Do the math.
 
VR sports coverage - even moreso.
 
 


On Monday, December 4, 2017 7:44am, "Mikael Abrahamsson" <swmike@swm.pp.se> said:



> On Mon, 4 Dec 2017, Pedro Tumusok wrote:
> 
> > Looking at chipsets coming/just arrived from the chipset vendors, I think
> > we will see CPE with 10G SFP+ and 802.11ax Q3/Q4 this year.
> > Price is of course a bit steeper than the 15USD USB DSL modem :P, but
> > probably fits nicely for the SMB segment.
> 
> https://kb.netgear.com/31408/What-SFP-modules-are-compatible-with-my-Nighthawk-X10-R9000-router
> 
> This has been available for a while now. Only use-case I see for it is
> Comcast 2 gigabit/s service, that's the only one I know of that would fit
> this product (since it has no downlink 10GE ports).
> 
> --
> Mikael Abrahamsson email: swmike@swm.pp.se
> _______________________________________________
> Cerowrt-devel mailing list
> Cerowrt-devel@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/cerowrt-devel
> 

[-- Attachment #2: Type: text/html, Size: 6301 bytes --]