[Cerowrt-devel] Dave Täht quoted in the ACLU blog

[Cerowrt-devel] Dave Täht quoted in the ACLU blog

[Rich Brown]

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See the second paragraph of:

https://www.aclu.org/blog/technology-and-liberty/we-want-internet-providers-respond-internet-demand-not-shape-it

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Re: [Cerowrt-devel] Dave Täht quoted in the ACLU blog

[Dave Taht]

A little out of context. I'd had a string of private convos with
robert trying to explain how peering worked before he'd written the
wired article, trying to get him to understand aqm and fair queuing
also.

As for the key misconception in the debate between level3, netflix, and isps...

 What I basically had said was that "the service provider, netflix in
this instance, had to pay someone to host their servers, cover the
cost of electricity and the cost of a port on big fat ethernet switch,
and it didn't matter if they paid a middleman like level3 for the
connectivity, OR an ISP that hosted the box on their internal
network."

It happens to be most cost-effective, if you have enough traffic, to
co-locate with the ISP. AND, in most cases, since that's cheaper to
the ISP than a middleman, ISPs have traditionally offered rack space
for free and the service provider covered the cost of the hardware,
the ISP is already getting paid by the customer, and the requirements
of the hardware and related capex and maintence costs by the service
provider.

Now, an argument can be made that the service provider  should also
pay for the rack space and electricity to the ISP, the same as if they
were co-located elsewhere and connected to a middleman, - and in *that
case* some regulation in order to ensure a fair market seems
necessary. (but it's also a hassle... and

later on in this debate, gfiber published their policies for
co-locating services like netflix in their datacenters, which made
that point more clearly, and explicitly laid out their policies to the
possible political detriment of the ISPs making the argument above.

 http://googlefiberblog.blogspot.com/2014/05/minimizing-buffering.html

Still, the points I made about congestion control, aqm and fair
queuing weren't made with the ACLU and I suppose I should go over
there to make those portions of my points, because the darn fast
lane/slow lane analogy is seriously flawed in general. Internet
traffic looks nothing like vehicular traffic.



On Tue, Jun 24, 2014 at 11:51 AM, Rich Brown <richb.hanover@gmail.com> wrote:
> See the second paragraph of:
>
> https://www.aclu.org/blog/technology-and-liberty/we-want-internet-providers-respond-internet-demand-not-shape-it
>
> _______________________________________________
> Cerowrt-devel mailing list
> Cerowrt-devel@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/cerowrt-devel
>



-- 
Dave Täht

NSFW: https://w2.eff.org/Censorship/Internet_censorship_bills/russell_0296_indecent.article

Re: [Cerowrt-devel] [Bloat] Dave Täht quoted in the ACLU blog

[Steinar H. Gunderson]

On Tue, Jun 24, 2014 at 12:29:34PM -0700, Dave Taht wrote:
> Still, the points I made about congestion control, aqm and fair
> queuing weren't made with the ACLU and I suppose I should go over
> there to make those portions of my points, because the darn fast
> lane/slow lane analogy is seriously flawed in general.

Well, once you talk about QoS (as opposed to paid peering or colocation),
it's not that bad.

/* Steinar */
-- 
Homepage: http://www.sesse.net/

Re: [Cerowrt-devel] Dave Täht quoted in the ACLU blog

[Dave Taht]

On Tue, Jun 24, 2014 at 12:29 PM, Dave Taht <dave.taht@gmail.com> wrote:
> A little out of context. I'd had a string of private convos with
> robert trying to explain how peering worked before he'd written the
> wired article, trying to get him to understand aqm and fair queuing
> also.
>
> As for the key misconception in the debate between level3, netflix, and isps...
>
>  What I basically had said was that "the service provider, netflix in
> this instance, had to pay someone to host their servers, cover the
> cost of electricity and the cost of a port on big fat ethernet switch,
> and it didn't matter if they paid a middleman like level3 for the
> connectivity, OR an ISP that hosted the box on their internal
> network."
>
> It happens to be most cost-effective, if you have enough traffic, to
> co-locate with the ISP. AND, in most cases, since that's cheaper to
> the ISP than a middleman, ISPs have traditionally offered rack space
> for free and the service provider covered the cost of the hardware,
> the ISP is already getting paid by the customer, and the requirements
> of the hardware and related capex and maintence costs by the service
> provider.
>
> Now, an argument can be made that the service provider  should also
> pay for the rack space and electricity to the ISP, the same as if they
> were co-located elsewhere and connected to a middleman, - and in *that
> case* some regulation in order to ensure a fair market seems
> necessary. (but it's also a hassle... and
>
> later on in this debate, gfiber published their policies for
> co-locating services like netflix in their datacenters, which made
> that point more clearly, and explicitly laid out their policies to the
> possible political detriment of the ISPs making the argument above.
>
>  http://googlefiberblog.blogspot.com/2014/05/minimizing-buffering.html
>
> Still, the points I made about congestion control, aqm and fair
> queuing weren't made with the ACLU and I suppose I should go over
> there to make those portions of my points, because the darn fast
> lane/slow lane analogy is seriously flawed in general. Internet
> traffic looks nothing like vehicular traffic.

I'd also (I think) made the point that I didn't like how all these services and
ISPS were becoming centralized, and if we wanted true neutrality, restrictive
rules by the ISPs regarding their customers hosting services of their own
had to go - and nobody's been making THAT point, which irks me significantly.

In an age where you have, say, gbit fiber to your business, it makes quite
a lot of sense from a security and maintenence perspective
to be hosting your own data and servers on your own darn premise, not
elsewhere.

I didn't make any points about competitiveness either; that was robert's piece.

For the record:

I oppose the time warner merger, and also oppose rules and regulations
that prevent municipalities from running their own fiber and allowing
providers to compete on top of it. In fact I strongly, strongly favor
the latter. I came very close to writing a letter to the FCC on that,
but didn't.

(I LIKED the world we had in the 90s with tens of thousands of ISPs competing
 on top of universally agreed upon link technologies. I ran one of those ISPs)

I am glad gfiber exists to put a scare into certain monopolists, but
even then I'd be tons happier if municipalities treated basic wired
connectivity as we do roads. One of the great "Secrets" of silicon
valley is it got wired for fiber early, through the vision and
foresight of people like Brian Reid and everybody got easy access.

Lastly, it is one of my hopes that one day wireless technologies would
become sufficiently robust to break the last wire monopolies once and
for all.

Great, now I'm grumpy...



>
> On Tue, Jun 24, 2014 at 11:51 AM, Rich Brown <richb.hanover@gmail.com> wrote:
>> See the second paragraph of:
>>
>> https://www.aclu.org/blog/technology-and-liberty/we-want-internet-providers-respond-internet-demand-not-shape-it
>>
>> _______________________________________________
>> Cerowrt-devel mailing list
>> Cerowrt-devel@lists.bufferbloat.net
>> https://lists.bufferbloat.net/listinfo/cerowrt-devel
>>
>
>
>
> --
> Dave Täht
>
> NSFW: https://w2.eff.org/Censorship/Internet_censorship_bills/russell_0296_indecent.article



-- 
Dave Täht

NSFW: https://w2.eff.org/Censorship/Internet_censorship_bills/russell_0296_indecent.article

Re: [Cerowrt-devel] [Bloat] Dave Täht quoted in the ACLU blog

[Rick Jones]

On 06/24/2014 12:45 PM, Dave Taht wrote:
> In an age where you have, say, gbit fiber to your business, it makes quite
> a lot of sense from a security and maintenence perspective
> to be hosting your own data and servers on your own darn premise, not
> elsewhere.

Perhaps, but where does having gigabit fibre to a business imply the 
business has the space, power, and cooling to host all the servers it 
might need/wish to have?

> I am glad gfiber exists to put a scare into certain monopolists, but
> even then I'd be tons happier if municipalities treated basic wired
> connectivity as we do roads. One of the great "Secrets" of silicon
> valley is it got wired for fiber early, through the vision and
> foresight of people like Brian Reid and everybody got easy access.

That must be a really well-kept secret as I am aware of no fibre running 
to my house in Sunnyvale :)

rick jones
speaking for myself alone

Re: [Cerowrt-devel] [Bloat] Dave Täht quoted in the ACLU blog

[Dave Taht]

On Tue, Jun 24, 2014 at 1:01 PM, Rick Jones <rick.jones2@hp.com> wrote:
> On 06/24/2014 12:45 PM, Dave Taht wrote:
>>
>> In an age where you have, say, gbit fiber to your business, it makes quite
>> a lot of sense from a security and maintenence perspective
>> to be hosting your own data and servers on your own darn premise, not
>> elsewhere.
>
>
> Perhaps, but where does having gigabit fibre to a business imply the
> business has the space, power, and cooling to host all the servers it might
> need/wish to have?

I didn't say there aren't compelling reasons also to co-locate in a data center,
but for many uses today, being able to host a basic website, some service,
email, etc at your own location, is perfectly doable, and possibly
preferable to co-locating places where things like this are happening:

http://fish2.com/ipmi/

or this:

http://en.wikipedia.org/wiki/Room_641A

>
>
>> I am glad gfiber exists to put a scare into certain monopolists, but
>> even then I'd be tons happier if municipalities treated basic wired
>> connectivity as we do roads. One of the great "Secrets" of silicon
>> valley is it got wired for fiber early, through the vision and
>> foresight of people like Brian Reid and everybody got easy access.
>
>
> That must be a really well-kept secret as I am aware of no fibre running to
> my house in Sunnyvale :)

The fiber loop around palo alto has quite the inspiring story behind
it. Maybe brian will
write it down one day, or already has.

http://en.wikipedia.org/wiki/Brian_Reid_(computer_scientist)


> rick jones
> speaking for myself alone



-- 
Dave Täht

NSFW: https://w2.eff.org/Censorship/Internet_censorship_bills/russell_0296_indecent.article

Re: [Cerowrt-devel] [Bloat] Dave Täht quoted in the ACLU blog

[Michael Richardson]

Rick Jones <rick.jones2@hp.com> wrote:
    > Perhaps, but where does having gigabit fibre to a business imply the business
    > has the space, power, and cooling to host all the servers it might need/wish
    > to have?

That's a secondary decision.
Given roof space, solar panels and/or snow-outside, maybe the answer is that
I regularly have 2 our of 3 of those available in a decentralized way.

And, how can I "cloudburst" (migrate some VMs from business to cloud and
back) if I don't have multi-gigabit fiber to the DC?

--
]               Never tell me the odds!                 | ipv6 mesh networks [
]   Michael Richardson, Sandelman Software Works        | network architect  [
]     mcr@sandelman.ca  http://www.sandelman.ca/        |   ruby on rails    [

Re: [Cerowrt-devel] [Bloat] Dave Täht quoted in the ACLU blog

[Dave Taht]

I burned an hour ranting over there. Naturally on the post, I got a
javascript error. I miss netnews.

On Tue, Jun 24, 2014 at 1:08 PM, Dave Taht <dave.taht@gmail.com> wrote:
> On Tue, Jun 24, 2014 at 1:01 PM, Rick Jones <rick.jones2@hp.com> wrote:
>> On 06/24/2014 12:45 PM, Dave Taht wrote:
>>>
>>> In an age where you have, say, gbit fiber to your business, it makes quite
>>> a lot of sense from a security and maintenence perspective
>>> to be hosting your own data and servers on your own darn premise, not
>>> elsewhere.
>>
>>
>> Perhaps, but where does having gigabit fibre to a business imply the
>> business has the space, power, and cooling to host all the servers it might
>> need/wish to have?
>
> I didn't say there aren't compelling reasons also to co-locate in a data center,
> but for many uses today, being able to host a basic website, some service,
> email, etc at your own location, is perfectly doable, and possibly
> preferable to co-locating places where things like this are happening:
>
> http://fish2.com/ipmi/
>
> or this:
>
> http://en.wikipedia.org/wiki/Room_641A
>
>>
>>
>>> I am glad gfiber exists to put a scare into certain monopolists, but
>>> even then I'd be tons happier if municipalities treated basic wired
>>> connectivity as we do roads. One of the great "Secrets" of silicon
>>> valley is it got wired for fiber early, through the vision and
>>> foresight of people like Brian Reid and everybody got easy access.
>>
>>
>> That must be a really well-kept secret as I am aware of no fibre running to
>> my house in Sunnyvale :)
>
> The fiber loop around palo alto has quite the inspiring story behind
> it. Maybe brian will
> write it down one day, or already has.
>
> http://en.wikipedia.org/wiki/Brian_Reid_(computer_scientist)
>
>
>> rick jones
>> speaking for myself alone
>
>
>
> --
> Dave Täht
>
> NSFW: https://w2.eff.org/Censorship/Internet_censorship_bills/russell_0296_indecent.article



-- 
Dave Täht

NSFW: https://w2.eff.org/Censorship/Internet_censorship_bills/russell_0296_indecent.article

Re: [Cerowrt-devel] [Bloat] Dave Täht quoted in the ACLU blog

[David Lang]

On Tue, 24 Jun 2014, Michael Richardson wrote:

> Rick Jones <rick.jones2@hp.com> wrote:
>    > Perhaps, but where does having gigabit fibre to a business imply the business
>    > has the space, power, and cooling to host all the servers it might need/wish
>    > to have?
>
> That's a secondary decision.
> Given roof space, solar panels and/or snow-outside, maybe the answer is that
> I regularly have 2 our of 3 of those available in a decentralized way.

given the amount of processing capacity that you can get today in a pasively 
cooled system, you can do quite a bit of serving from a small amount of space 
and power.

The days when it took rooms of Sun boxes to saturate a Gb line are long gone, 
you can do that with just a handful of machines.

David Lang

Re: [Cerowrt-devel] [Bloat] Dave Täht quoted in the ACLU blog

[David P. Reed]

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Maybe I am misunderstanding something... it just took my Mac book Pro doing an rsync to copy a TB of data from a small NAS  at work yesterday to get about 700 Gb/sec on a GigE office network for hours yesterday.

I had to do that in our Santana Clara office rather than from home outside Boston, which is where I work 90% of the time.

That's one little computer and one user...

What does my Mac Book Pro draw doing that? 80 Watts?

On Jun 27, 2014, David Lang <david@lang.hm> wrote:
>On Tue, 24 Jun 2014, Michael Richardson wrote:
>
>> Rick Jones <rick.jones2@hp.com> wrote:
>>    > Perhaps, but where does having gigabit fibre to a business imply
>the business
>>    > has the space, power, and cooling to host all the servers it
>might need/wish
>>    > to have?
>>
>> That's a secondary decision.
>> Given roof space, solar panels and/or snow-outside, maybe the answer
>is that
>> I regularly have 2 our of 3 of those available in a decentralized
>way.
>
>given the amount of processing capacity that you can get today in a
>pasively 
>cooled system, you can do quite a bit of serving from a small amount of
>space 
>and power.
>
>The days when it took rooms of Sun boxes to saturate a Gb line are long
>gone, 
>you can do that with just a handful of machines.
>
>David Lang
>_______________________________________________
>Cerowrt-devel mailing list
>Cerowrt-devel@lists.bufferbloat.net
>https://lists.bufferbloat.net/listinfo/cerowrt-devel

-- Sent from my Android device with K-@ Mail. Please excuse my brevity.

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Re: [Cerowrt-devel] [Bloat] Dave Täht quoted in the ACLU blog

[Dave Taht]

On Fri, Jun 27, 2014 at 9:06 PM, David P. Reed <dpreed@reed.com> wrote:
> Maybe I am misunderstanding something... it just took my Mac book Pro doing
> an rsync to copy a TB of data from a small NAS  at work yesterday to get
> about 700 Gb/sec on a GigE office network for hours yesterday.
>
> I had to do that in our Santana Clara office rather than from home outside
> Boston, which is where I work 90% of the time.
>
> That's one little computer and one user...

On a daily basis, the bufferbloat websites transfer far, far less than gigE

IF the redmine portion of the site wasn't so cpu expensive, I could
use something
other than hefty boxes they are on. Similarly snapon's cpu is mostly
used for builds, the file transfer role could be done by something else
easily. I'd like to switch it over to do that one day.

> What does my Mac Book Pro draw doing that? 80 Watts?

I love the "kill-a-watt" products. I use them everywhere. (while I'm
pimping stuff I like, digilogger's power switches are a lifesaver also -
staging boots for devices that draw a lot of power in a tiny lab that
can only draw 350 watts before becoming a fire hazard)

Your NAS probably ate less than 16 watts, more if you have more than one drive.

My nucs draw 18 watts and can transfer at GigE off a flash disk
without raising a sweat.
(at least some of your overhead is in the rsync protocol, which is
overly chatty)

Several tiny arm boards can all do gigE at line rate, notably stuff built around
marvell and cavium's chipset(s), and they do it at under 2 watts. Most support
64GB mini-sd cards (with pretty lousy transfer rates).

Pretty sure (haven't booted it yet) the parallella (which is smaller
than a drive),
can do it in under a 2 watt, and if it doesn't do gigE now, it'll do
it after I get through
with it - but it lacks a sata port, and usb is only 2.0, so it might
not drive gigE
from a nas perspective. (It kind of bugs me that most of the tiny boards are in
the altoids form factor, rather than the 2.5 inch drive form factor)

So I go back to my original point in that, once you have fiber to the business,
for most purposes in a small business or startup or home - who needs
to co-lo in a data center?
You can have a tiny wart on the wall do most of the job. And that's
today. In another
year or so we'll be over some more tipping points.

One thing that does bug me is most UPSes are optimized to deliver a large
load over a short time, a UPS capable of driving 5 watts for, say, 3 days is
kind of rare.

> On Jun 27, 2014, David Lang wrote:
>>
>> On Tue, 24 Jun 2014, Michael Richardson wrote:
>>
>>> Rick Jones wrote:
>>>>
>>>> Perhaps, but where does having gigabit fibre to a business imply the
>>>> business
>>>> has the space, power, and cooling to host all the servers it might
>>>> need/wish
>>>> to have?
>>>
>>>
>>> That's a secondary decision.
>>> Given roof space, solar panels and/or snow-outside, maybe the answer is
>>> that
>>> I regularly have 2 our of 3 of those available in a decentralized way.
>>
>>
>> given the amount of processing capacity that you can get today in a
>> pasively
>> cooled system, you can do quite a b it of serving from a small amount of
>> space
>> and power.
>>
>> The days when it took rooms of Sun boxes to saturate a Gb line are long
>> gone,
>> you can do that with just a handful of machines.
>>
>> David Lang
>> ________________________________
>>
>> Cerowrt-devel mailing list
>> Cerowrt-devel@lists.bufferbloat.net
>> https://lists.bufferbloat.net/listinfo/cerowrt-devel
>
>
> -- Sent from my Android device with K-@ Mail. Please excuse my brevity.
>
> _______________________________________________
> Bloat mailing list
> Bloat@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/bloat
>



-- 
Dave Täht

NSFW: https://w2.eff.org/Censorship/Internet_censorship_bills/russell_0296_indecent.article

[Cerowrt-devel] Low Power UPSes (Was: Re: [Bloat] Dave Täht quoted in the ACLU blog)

[Joseph Swick]

On 06/28/2014 12:28 AM, Dave Taht wrote:
> Pretty sure (haven't booted it yet) the parallella (which is smaller
> than a drive),
> can do it in under a 2 watt, and if it doesn't do gigE now, it'll do
> it after I get through
> with it - but it lacks a sata port, and usb is only 2.0, so it might
> not drive gigE
> from a nas perspective. (It kind of bugs me that most of the tiny boards are in
> the altoids form factor, rather than the 2.5 inch drive form factor)
> 
> So I go back to my original point in that, once you have fiber to the business,
> for most purposes in a small business or startup or home - who needs
> to co-lo in a data center?
> You can have a tiny wart on the wall do most of the job. And that's
> today. In another
> year or so we'll be over some more tipping points.
> 
> One thing that does bug me is most UPSes are optimized to deliver a large
> load over a short time, a UPS capable of driving 5 watts for, say, 3 days is
> kind of rare.
> 

I think this is something that's in need of a new approach/disruption.
For low power devices like NUCs and RasPi servers, running them off of a
traditional UPS is hugely waste-full, since you're going from your Line
voltage (120VAC or 240VAC in many places) to 12 or 24VDC (Or 48VDC for a
bigger UPS).  Then when the UPS has to kick in, it converts the battery
voltage back to your line voltage.

A better approach would be to have a UPS that had a good intelligent
charger for your deep-cycle type battery that coming off the battery,
you kept it at the correct DC level for your NUC or Raspi.  Which for
many of these devices is 5 or 12VDC.  So in a sense, it becomes your
low-power device's power suppy, it just happens to have the added
benefit of having a built-in backup battery.

Coming from a Ham Radio perspective, some hams run their base stations
off of deep-cycle marine batteries with some form of charger keeping
them topped off.  This way, the radio operator can operate his or her
station for days just on emergency power.  Since a lot of ham gear is
designed to operate off of 12VDC (with some notable exceptions like your
high-power amplifiers).

It shouldn't be hard to develop a decent grade Low-power UPS for home or
small office use that can run these low power devices for days at a time
with out all the inefficiencies of converting VAC to VDC and back again.
 And there's probably a bunch of Raspi (or similar low-power computer
boards) enthusiasts who already have for their own personal use.

- Joseph Swick

Re: [Cerowrt-devel] [Bloat] Dave Täht quoted in the ACLU blog

[Theodore Ts'o]

On Fri, Jun 27, 2014 at 09:28:55PM -0700, Dave Taht wrote:
> 
> So I go back to my original point in that, once you have fiber to
> the business, for most purposes in a small business or startup or
> home - who needs to co-lo in a data center?  You can have a tiny
> wart on the wall do most of the job. And that's today. In another
> year or so we'll be over some more tipping points.

For many people, the reason why they use a colo is not just because of
network access.  And it's not just about power.  Sure, if you're just
sending unencrypted data off of a flash drive it's not going to take
much power to saturate a GigE.  But if you're going to be running a
real server, with a backend database, and doing some real
transactional processing, you might not use a whole lot of network
bandwidth, but it still might be using enough power, space, and
generate enough noise, that you might want to use a colo.

Also, historically, most people didn't have stable IPv4 addresses
provided by their ISP.  So if you wanted to run a server, you had to
use a colo.  With IPv6, this will hopefully change, but an ISP might
still not be willing to give you a long-term stable IPv6 address
assignment.

					 - Ted

Re: [Cerowrt-devel] Low Power UPSes (Was: Re: [Bloat] Dave Täht quoted in the ACLU blog)

[David Lang]

On Sat, 28 Jun 2014, Joseph Swick wrote:

> On 06/28/2014 12:28 AM, Dave Taht wrote:
>>
>> One thing that does bug me is most UPSes are optimized to deliver a large
>> load over a short time, a UPS capable of driving 5 watts for, say, 3 days is
>> kind of rare.
>>
>
> I think this is something that's in need of a new approach/disruption.
> For low power devices like NUCs and RasPi servers, running them off of a
> traditional UPS is hugely waste-full, since you're going from your Line
> voltage (120VAC or 240VAC in many places) to 12 or 24VDC (Or 48VDC for a
> bigger UPS).  Then when the UPS has to kick in, it converts the battery
> voltage back to your line voltage.
>
> A better approach would be to have a UPS that had a good intelligent
> charger for your deep-cycle type battery that coming off the battery,
> you kept it at the correct DC level for your NUC or Raspi.  Which for
> many of these devices is 5 or 12VDC.  So in a sense, it becomes your
> low-power device's power suppy, it just happens to have the added
> benefit of having a built-in backup battery.
>
> Coming from a Ham Radio perspective, some hams run their base stations
> off of deep-cycle marine batteries with some form of charger keeping
> them topped off.  This way, the radio operator can operate his or her
> station for days just on emergency power.  Since a lot of ham gear is
> designed to operate off of 12VDC (with some notable exceptions like your
> high-power amplifiers).
>
> It shouldn't be hard to develop a decent grade Low-power UPS for home or
> small office use that can run these low power devices for days at a time
> with out all the inefficiencies of converting VAC to VDC and back again.
> And there's probably a bunch of Raspi (or similar low-power computer
> boards) enthusiasts who already have for their own personal use.

I think a lot of people are just using li battery packs with USB output to run 
their Pi type computers, with a wall charger into the battery pack.

it may not be the best thing for the batteries, but it's off-the-shelf and 
cheap.

for 12v computers, it's easy to just float a gell-cell on the output of a power 
supply. If you want to be a purist, have some sort of current limiting resister 
so that when the battery is extremely low you don't overload the power supply, 
but in practice, the power supplies are cheap (getting hold of an old PC power 
supply is probably free, and they tend to have a fairly heafty 12v output), and 
gell cells are pretty forgiving of abuse, so you can get away with the 
dirt-simple PS -> battery -> device the vast majority of the time.

It helps that "12v" equipment tends to actually be speced to run off of 
automotive power, which is about the ugliest power source you can deal with.

David Lang

Re: [Cerowrt-devel] Low Power UPSes (Was: Re: [Bloat] Dave Täht quoted in the ACLU blog)

[dpreed]

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Good suggestions.  Also, if you have 12V charging the relevant battery, you can power 5V stuff with a cheap, off-the-shelf UBEC.  In a system I built recently, I powered a Wandboard, an SSD (SSD's typically only use their 5V supply) and an 8 port GigE desktop switch with one that puts out 5@5V:
 
http://www.robotmarketplace.com/products/0-DYS30055.html.
 
There are lots of UBEC's out there in the robotics and radio control suppliers. Motors and batteries like to be higher than 5V, and the electronics and small servos like 5V.  You could design your own, but why bother...
 
 
 


On Sunday, June 29, 2014 11:45pm, "David Lang" <david@lang.hm> said:



> On Sat, 28 Jun 2014, Joseph Swick wrote:
> 
> > On 06/28/2014 12:28 AM, Dave Taht wrote:
> >>
> >> One thing that does bug me is most UPSes are optimized to deliver a
> large
> >> load over a short time, a UPS capable of driving 5 watts for, say, 3 days
> is
> >> kind of rare.
> >>
> >
> > I think this is something that's in need of a new approach/disruption.
> > For low power devices like NUCs and RasPi servers, running them off of a
> > traditional UPS is hugely waste-full, since you're going from your Line
> > voltage (120VAC or 240VAC in many places) to 12 or 24VDC (Or 48VDC for a
> > bigger UPS). Then when the UPS has to kick in, it converts the battery
> > voltage back to your line voltage.
> >
> > A better approach would be to have a UPS that had a good intelligent
> > charger for your deep-cycle type battery that coming off the battery,
> > you kept it at the correct DC level for your NUC or Raspi. Which for
> > many of these devices is 5 or 12VDC. So in a sense, it becomes your
> > low-power device's power suppy, it just happens to have the added
> > benefit of having a built-in backup battery.
> >
> > Coming from a Ham Radio perspective, some hams run their base stations
> > off of deep-cycle marine batteries with some form of charger keeping
> > them topped off. This way, the radio operator can operate his or her
> > station for days just on emergency power. Since a lot of ham gear is
> > designed to operate off of 12VDC (with some notable exceptions like your
> > high-power amplifiers).
> >
> > It shouldn't be hard to develop a decent grade Low-power UPS for home or
> > small office use that can run these low power devices for days at a time
> > with out all the inefficiencies of converting VAC to VDC and back again.
> > And there's probably a bunch of Raspi (or similar low-power computer
> > boards) enthusiasts who already have for their own personal use.
> 
> I think a lot of people are just using li battery packs with USB output to run
> their Pi type computers, with a wall charger into the battery pack.
> 
> it may not be the best thing for the batteries, but it's off-the-shelf and
> cheap.
> 
> for 12v computers, it's easy to just float a gell-cell on the output of a power
> supply. If you want to be a purist, have some sort of current limiting resister
> so that when the battery is extremely low you don't overload the power supply,
> but in practice, the power supplies are cheap (getting hold of an old PC power
> supply is probably free, and they tend to have a fairly heafty 12v output), and
> gell cells are pretty forgiving of abuse, so you can get away with the
> dirt-simple PS -> battery -> device the vast majority of the time.
> 
> It helps that "12v" equipment tends to actually be speced to run off of
> automotive power, which is about the ugliest power source you can deal with.
> 
> David Lang
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