iperf 2 uses responses per second and also provides the bounce back
times as well as one way delays.
The hypothesis is that network engineers have to fix KPI issues,
including latency, ahead of shipping products.
Asking companies to act on consumer complaints is way too late. It's
also extre
for completeness, here is a concurrent "working load" example:
[root@ryzen3950 iperf2-code]# iperf -c 192.168.1.58%enp4s0 -i 1 -e
--bounceback --working-load=up,4 -t 3
Client connecting to 192.168.1.58, TCP port 5001 with pid 3125575
Our current WiFi designs, at least in residential, are like garden hoses
attached to rectangular sprinklers - flexible and suboptimal. What's
needed is an irrigation system approach where physical dimensions and
spray patterns are designed in by a qualified designer. (I was 16 when I
got my Tex
[SM] not really, given enough capacity, typical streaming protocols
will actually not hit the ceiling, at least the one's I look at every
now and then tend to stay well below actual capacity of the link.
I think DASH type protocol will hit link peaks. An example with iperf
2's burst opti
On 2023-03-13 11:51, Sebastian Moeller wrote:
Hi Bob,
On Mar 13, 2023, at 19:42, rjmcmahon wrote:
[SM] not really, given enough capacity, typical streaming protocols
will actually not hit the ceiling, at least the one's I look at every
now and then tend to stay well below actual cap
[SM] It is doe because:
a) TCP needs some capacity estimate
b) preferably quickly
c) in a way gentler than what was used before the congestion collapse.
Right, but we're moving away from capacity shortages to a focus on
better latencies. The speed of distributed compute (or speed of
ca
To change the topic - curious to thoughts on FiWi.
Imagine a world with no copper cable called FiWi (Fiber,VCSEL/CMOS
Radios, Antennas) and which is point to point inside a building
connected to virtualized APs fiber hops away. Each remote radio head
(RRH) would consume 5W or less and only whe
The design has to be flexible so DIY w/local firewall is fine.
I'll disagree though that early & late majority care about firewalls.
They want high-quality access that is secure & private. Both of these
require high skill network engineers on staff. DIY is hard here.
Intrusion detection system
I am old fashioned this way, also, but I think most modern users would
not care, any more about this. They are used to pretty much having all
their data exposed to the internet, available via cellphone, and used
to having their security cameras and other personal information, gone,
out there.
The
It's based upon 802.11be which is quite extensive
https://en.wikipedia.org/wiki/IEEE_802.11be
Bob
I wonder where that number comes from?
https://www.engadget.com/netgears-first-wifi-7-router-offers-extra-low-latency-for-gaming-123037814.html
My joy in seeing this, is not in what the actual un
The 6G is a contiguous 1200MhZ. It has low power indoor (LPI) and very
low power (VLP) modes. The pluggable transceiver could be color coded to
a chanspec, then the four color map problem can be used by installers
per those chanspecs. https://en.wikipedia.org/wiki/Four_color_theorem
There is n
My brother and I installed irrigation systems in Texas where it rains a
lot. No problem with getting business. Digging trenches, laying & gluing
PVC pipe, installing controller wires, etc is good, respectable work.
I wonder if too many white-collar workers avoided blue-collar work and
don't un
Agreed, AQM is like an emergency brake. Go ahead and keep it but hope to
never need to use it.
Bob
Hi Bob,
I like your design sketch and the ideas behind it.
On Mar 15, 2023, at 18:32, rjmcmahon via Bloat
wrote:
The 6G is a contiguous 1200MhZ. It has low power indoor (LPI) and very
low
I have sometimes thought that LiFi (https://lifi.co/) would suddenly
come out of the woodwork,
and we would be networking over that through the household.
I think the wishful thinking is "coming from woodwork" vs coming from
the current and near future state of engineering. Engineering comes fr
the financial drivers that the
unconnected really operate under, on top of IT literacy, digital
skills, devices, power...
Best,
Mike
On Mar 14, 2023 at 05:27 +0100, rjmcmahon via Starlink
, wrote:
To change the topic - curious to thoughts on FiWi.
Imagine a world with no copper cable called
Monitoring the
groundwater with samples every 4 mos is ok - better to monitor the
structure itself 24x7x365.
https://www.sciencedirect.com/topics/engineering/digital-image-correlation
https://www.bostongroundwater.org/
Bob
On 2023-03-17 13:37, Bruce Perens wrote:
On Fri, Mar 17, 2023 a
I'm curious as to why the detectors have to be replaced every 10
years.
Dust, grease from cooking oil vapors, insects, mold, etc. accumulate,
and it's so expensive to clean those little sensors, and there is so
much liability associated with them, that it's cheaper to replace the
head every 10 y
> All of the states use cases are already handled by inexpensive
lorawan
sensors and are already covered by multiple lorawan networks in NYC
and most urban centers in the US. There is no need for a new
infrastructure, it’s already there. Not to mention NBIoT/catm
radios.
This is all just gene
Hi All,
It seems getting the metrics right is critical. Our industry can't be
reporting things that mislead or misassign blame. The medical community
doesn't treat people for cancer without having a high degree they've
gotten the diagnostics correct as an example.
An initial metric, per this
If I'm reading things correctly, the per fire alarm power rating is 120V
at 80 mA or 9.6 W. The per power FiWi transceiver estimate is 2 Watts
per spatial stream at 160MhZ and 1 Watt for the fiber. Looks like a
retrofit of a fire alarm system would have sufficient power for FiWi
radio heads. Th
I was around when BGP & other critical junctures
https://en.wikipedia.org/wiki/Critical_juncture_theory the commercial
internet. Here's a short write-up from another thread with some thoughts
(Note: there are no queues in the Schramm Model
https://en.wikipedia.org/wiki/Schramm%27s_model_of_com
To be fair, this isn't unique to Comcast. I hit similar issues in NYC
with Verizon.
I think we really need to educate people that life support capable
communications networks are now critical infrastructure.
And, per climate impact, we may want to add Jaffe's network power
(capacity over del
It's not just one phone call. I've been figuring this out for about two
years now. I've been working with some strategic people in Boston, colos
& dark fiber providers, and professional installers that wired up many
of the Boston universities, some universities themselves to offer co-ops
to stu
t standard of
installation. If this mattered enough to your homeowners association,
they could pay for it.
On Sat, Mar 25, 2023, 12:39 rjmcmahon via Starlink
wrote:
Hi All,
I've been trying to modernize a building in Boston where I'm an HOA
board member over the last 18 mos. I pe
On who pays & does the internal wiring: I agree & agree. This is a capex
spend and asset improvement so payments come from the property owner(s)
somehow. My thoughts are this is a new industry for the trades. My
interactions with many in their 20s suggest that starting or working for
a fiber &
I don't think so. The govt. just bailed out SVB for billionaires who
were woefully underinsured. The claim is that it protected our financial
system. Their risk officers didn't price in inflation and those impacts,
i.e. they eliminated insurance without eliminating the liability.
Texas govt se
Thanks for this. Yeah, I can understand MDUs are complex and present
unique issues for both their Boards and companies to service them.
Condo trusts, LLC non profits, co-ops, etc. Too many attorneys to boot.
My attorney fees cost more than my training youth to install FiWi infra.
The expensive
Interesting. I'm skeptical that our cities in the U.S. can get this
(structural separation) right.
Pre-coaxial cable & contract carriage, the FCC licensed spectrum to the
major media companies and placed a news obligation on them for these OTA
rights. A society can't run a democracy well witho
There are municipal broadband projects. Most are in rural areas
partially funded by the federal government via the USDA. Glasgow started
a few decades ago. Similar to LUS in Lafayette, LA.
https://www.usda.gov/broadband
Rural areas get a lot of federal money for things, a la the farm bill
whi
Agreed though, from a semiconductor perspective, 100K units over ten+
years isn't going to drive a foundry to produce the parts required.
Then, a small staff makes the same decisions for all 100K premises
regardless of things like the ability to pay for differentiators as they
have no different
If it doesn't align with privacy & security, what we know of physics,
what can be achieved by world class engineering, what will be funded by
market models or behaviors based upon payments & receipts, increase job
creation for blue collar workers, reduce power consumption, etc. then I
agree FiW
Hi Sebastian,
I'm fine with municipal broadband projects. I do think they'll need to
leverage the economy of scale driven by others. An ASIC tape out, just
for the design, is ~$80M and a minimum of 18 mos of high-skill,
engineering work by many specialties, signal integrity, etc. Then, after
Common Carriage goes way beyond our lifes. Eli Noam's write up in 1994
is a good one.
http://www.columbia.edu/dlc/wp/citi/citinoam11.html
Beyond Liberalization II:
The Impending Doom of Common Carriage
Eli M. Noam
Professor of Finance and Economics
Columbia University, Graduate School of Busine
Here's is the point for TLDR by Noam. Neutral traffic acceptance is not
no priorities. We want traffic priorities despite all the b.s. that
they're unfair.
"All of common carriages free-flow, goals of low transaction cost, and
no-liability goals are thus preserved by a system of (a) non-exclus
I think I'm being schedule to present iperf 2 to the FCC TAC sometime in
January 2024. I'll know more soon.
I plan to have a hands on session, going over
o) WiFi/Broadband key latency technologies
o) Iperf 2 tooling and metrics, including bloat (in units of memory)
o) A WiFi diagnostics latency
iperf 2 supports OWD in multiple forms.
A raspberry pi 5 has a realtime clock and hardware PTP and gpio PPS. The
retail cost for a pi5 with GPS atomic clock and active fan is less than
$150
[rjmcmahon@fedora iperf2-code]$ src/iperf -c 192.168.1.35 --bounceback
--trip-times --bounceback-peri
Hi All,
We're trying to modernize America. LBJ helped do it for electricity
decades ago. It's our turn to step up to the plate. Tele-health and
distance learning requires us to do so. There is so much to follow.
A reminder what many women went through before LBJ showed up. I'm
skeptical a pa
Women are the primary users and providers of telehealth services. They
are using broadband to care for our population. They also run most of
the addiction services across our country, whatever the addiction may
be. So gender actually matters. Ask them as providers. Telehealth
doesn't work over
I surveyed some female telehealth providers. There are a lot of
subtleties required to make telehealth work well for the providers.
Their knowledge level is quite fascinating.
I don't see their voices here on these boards either. In education, the
absence of something being taught is called th
The president who ran Harvey Mudd College had to fix their computer
science problem of a 90% to 10% male to female ratio. She was asked,
"What's the goal?" She responded, "It should reflect to population so
50/50." The others said, "Be realistic."
She was and she got it to 50/50 where it shoul
Thanks for sharing this. I'm trying to find out what are the key metrics
that will be used for this monitoring. I want to make sure iperf 2 can
cover the technical, traffic related ones that make sense to a skilled
network operator, including a WiFi BSS manager. I didn't read all 327
pages thou
I'm curious at what's needed by iperf here to help with connection
timeouts.
Bob
EXCERPT:
A Multifaceted Look at Starlink Performance
Nitinder Mohan∗ Technical University of Munich Germany
Andrew E. Ferguson∗ The University of Edinburgh United Kingdom
Hendrik Cech∗ Technical University of Mu
This isn't the definition of latency:
"Latency refers to the amount of time, usually measured in milliseconds,
that it takes for a packet to be sent from your Starlink router to the
internet and for the response to be received. This is also known as
“round-trip time”, or RTT."
Better is the
Here's one of Cisco's switch architects presenting what they did.
https://www.youtube.com/watch?v=YISujYcnbSI
They also have something called HULL, high occupancy low latency. The
idea is keep the arrival rates slightly under the service rates so
standing queues don't form. This was initially
One sample for a subgroup, from an SPC perspective, is typically
insufficient, e.g. Shewart control charts. Below are some suggestions:
https://bookdown.org/lawson/an_introduction_to_acceptance_sampling_and_spc_with_r26/shewhart-control-charts-in-phase-i.html
o) Define the subgroup size: Initia
Nice write up and work over the years.
On tooling:
iperf 2 supports full duplex, multiple parallel streams, tx start times,
bounceback, isochronous, etc. Man page is here
https://iperf2.sourceforge.io/iperf-manpage.html
The flows code in the flows directory
https://sourceforge.net/p/iperf2/
Hi Sebastian,
Per Aristotle: "That which is common to the greatest number gets the
least amount of care. Men pay most attention to what is their own: they
care less for what is common."
I think a challenge for many of us providing open source tooling is the
lack of resource support to supply
Thanks for the well-written response Sebastian. I need to think more
about the load vs no load OWD differentials and maybe offer that as an
integrated test. Thanks for bringing it up (again.) I do think a
low-duty cycle bounceback test to the AP could be interesting too.
I don't know of any pr
Curious to why people keep calling capacity tests speed tests? A semi at
55 mph isn't faster than a porsche at 141 mph because its load volume is
larger.
Bob
HNY Dave and all the rest,
Great to see yet another capacity test add latency metrics to the
results. This one looks like a good start.
auckland.ac.nz
http://www.cs.auckland.ac.nz/~ulrich/ [1]
---------
From: Starlink on behalf of
rjmcmahon via Starlink
Sent: Thursday, January 5, 2023 9:02 AM
To: j...@jonathanfoulkes.com
Cc: Cake List ; IETF IPPM WG
; l
Some thoughts are not to use UDP for testing here. Also, these speed
tests have little to no information for network engineers about what's
going on. Iperf 2 may better assist network engineers but then I'm
biased ;)
Running iperf 2 https://sourceforge.net/projects/iperf2/ with
--trip-times.
For responsiveness, the bounceback seems reasonable even with upstream
competition. Bunch more TCP retries though.
[rjmcmahon@ryzen3950 iperf2-code]$ iperf -c *** --hide-ips -e
--trip-times -i 1 --bounceback -t 3
Client connecting to
My biggest barrier is the lack of clock sync by the devices, i.e. very
limited support for PTP in data centers and in end devices. This limits
the ability to measure one way delays (OWD) and most assume that OWD is
1/2 and RTT which typically is a mistake. We know this intuitively with
airplane
User based, long duration tests seem fundamentally flawed. QoE for users
is driven by user expectations. And if a user won't wait on a long test
they for sure aren't going to wait minutes for a web page download. If
it's a long duration use case, e.g. a file download, then latency isn't
typical
The write to read latencies (OWD) are on the server side in CLT form.
Use --histograms on the server side to enable them.
Your client side sampled TCP RTT is 6ms with less than a 1 ms of
variance (or sqrt of variance as variance is typically squared) No
retries suggest the network isn't dropp
The target audience for iperf 2 latency metrics is network engineers and
not end users. My belief is that a latency complaint from an end user is
a defect escape, i.e. it should have been caught earlier by experts in
our industry. That's part of the reason why I think open source tooling
that i
A peer likes gnuplot and sed. There are many, many visualization tools.
An excerpt below:
My quick hack one-line parser was based on just a single line from the
iperf output, not the entire log:
[ 1] 0.00-1.00 sec T8-PDF:
bin(w=1ms):cnt(849)=1:583,2:112,3:9,4:8,5:11,6:10,7:7,8:8,9:7,10:2,11
Also released is python code. It's based on python 3's asyncio. It just
needs password-less ssh to be able to create the pipes. This opens up
the stats processing to a vast majority of tools used by data scientists
at large.
https://sourceforge.net/p/iperf2/code/ci/master/tree/flows/
https://d
of a technical issue.
Bob
Hello,
Yall can call me crazy if you want.. but... see below [RWG]
Hi Bib,
> On Jan 9, 2023, at 20:13, rjmcmahon via Starlink
wrote:
>
> My biggest barrier is the lack of clock sync by the devices, i.e. very limited
support for PTP in data centers
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