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Posted by Jack Crossfire | Aug 17, 2014 @ 05:30 PM | 2,081 Views



The long sought after bluetooth GPS hack was finally tested.



It was a complete failure.

...Continue Reading
Posted by Jack Crossfire | Aug 16, 2014 @ 06:50 PM | 2,180 Views
The latest theory was bandwidth limiting was the result of total usage + current bitrate going above a certain amount. If the current bitrate was always below a certain amount, maybe the total usage wouldn't be capped. The iwconfig rate command doesn't do anything anymore. The only way to limit your bitrate is now traffic shaping.

Traffic shaping in Linux is a very long, involved process, requiring in depth knowledge of the kernel. It's not supported on the phone itself. There is a tool called http://lartc.org/wondershaper/ which hard codes the most useful configuration. When run on the pi router, it successfully limits bandwidth between wlan0 & eth0, but not bandwidth between wlan0 & another station. It has to be run on every station to limit its own wlan interface.

Traffic shaping is not bulletproof. It can't limit the rate packets come from the internet, so it tries to limit the rate of ACK packets. Bandwidth still often goes above the limit, then settles below the limit once the window is full. The problem is easier on Virgin's side, since they're on the giving end of most of the data.
Posted by Jack Crossfire | Aug 16, 2014 @ 04:25 AM | 1,971 Views



So at 4am, after hitting 6.45GB & a stretch of 9 megabit downloading,



Bandwidth was finally cut down to 128kbit with an email saying 2.5GB was exceeded & the party was over until the next billing cycle. It was definitely strange timing.

The internet screams bloody murder whenever someone complains about unlimited plans not really being unlimited & how it's the corporation's right to cut you off for degrading the network performance, but look. Who's suffering from degraded network performance at 4am?

The solution to network performance is a priority queue. If the quota is exceeded, you put the user on the bottom of the queue. If the network is idle, they get the full bandwidth. If the network is full, they get reduced bandwidth. Voice calls have been prioritized higher than data for all time without requiring the data to be limited to 128kbit.

Bandwidth throttling has nothing to do with improving network performance, but is meant to force you to pay for a higher end plan. The idea makes sense in terms of profits, if you offer a higher end plan, but Virgin doesn't. They just offer 2.5GB plans.

The Goog shows Virgin trying many experiments in network management, from temporary throttling to upload throttling to peak hour throttling, but never the obvious priority queue. Maybe it's technologically unfeasible to achieve such prioritization, but Kiwipedia says it's a tried & true practice.

Virgin obviously can't figure out a solution or doesn't have any incentive to do the obvious. It's another time when easy solutions abound but easy money doesn't make them worth it, much like 20 years ago when IIS crashed constantly & no-one could bother with the easy solution of using apache & Linux.

Well, you're probably more productive in the current situation, but come the next interview or online course, it's going to be DSL.
Posted by Jack Crossfire | Aug 14, 2014 @ 09:05 PM | 1,985 Views
So you have a pi router with wlan0 & eth0. The internet is on a wlan0 address 10.0.1.11. The home network is on a eth0 address 10.0.0.11. Getting from a network on eth0 to a phone on wlan0 is a big deal. There are many ways to do it. There's using a bridge device on your pi to make eth0 & wlan0 the same device.

apt-get install bridge-utils

In /etc/hostapd/hostapd.conf add
bridge=br0
but keep
interface=wlan0

In /etc/init.d/ap add
brctl addbr br0
brctl addif br0 wlan0
brctl addif br0 eth0
ifconfig br0 10.0.0.11 netmask 255.255.255.0

The IP masquerading is the same. The IP addresses of wlan0 & eth0 need to be 0.0.0.0. Setting br0 sets both to the address of br0. Everyone on the wired network uses 10.0.0.11 as their gateway, which forwards everything to the phone. Bridging falls apart when you put more than 1 access point on the network.

Instead of a bridge, you need the wireless parts & the wired parts on different subnets. Every access point is a different subnet, while the wired part is the same. On the phone & every wireless computer, create a routing entry from the wireless subnet to the wired subnet.

/system/xbin/route add -net 10.0.0.0 netmask 255.255.255.0 gw 10.0.1.11

On every wired computer, create a routing entry from the wired subnet to the wireless subnet.

route add -net 10.0.1.0 netmask 255.255.255.0 gw 10.0.0.11

Everyone wanting to go to the other subnet needs a routing entry. Without the entry, it sometimes works,...Continue Reading
Posted by Jack Crossfire | Aug 12, 2014 @ 02:56 PM | 1,626 Views

It may seem strange to use a fragile optical fiber to move 1.4 megabits of data in this world of gigabit wireless, but it was cheaper than buying a new amplifier. Merely enable IEC958 on Mix2005 & the raw digital audio buffer goes straight to the amplifier. The amplifier automatically switches to its own DAC. There's no longer any level control on the computer, no more ground loop, & no more AC hum. The highs jump out a lot more. The amplifier seems to do the full 48khz.

It's probably the best sounding computer in the world, since no-one ever bothers connecting their computer to a decent speaker, let alone digitally. Computers were still supporting the 30 year old optical audio standard until 2010. There was never any need to bother with RCA cables, since the optical cable was $3. Nowadays, they all use bluetooth.

The next logical step was of course digital audio from the cp33 -> amplifier.


Time once again to open it up to flash a smaller fragment size. With the fragment sizes optimized as small as possible, the delay was estimated at 7ms. Unfortunately, it was a waste. The delay was noticeable. There was no difference in the amount of hiss. It probably wouldn't be robust enough to record anything. The experiment did reveal that Zone 1 changed amplitude in the digital stream, so all the recordings were overloaded. It still might be useful to eliminate ground loops.

Having never played with bluetooth audio besides the crappy old phone headsets, would assume bluetooth audio had the worst latency. USB standards compliant audio probably has the latency of a soundcard, with toslink still the only thing down to single sample latency.
Posted by Jack Crossfire | Aug 11, 2014 @ 05:30 PM | 1,751 Views

For the 1st time in history, someone overlaid the supermoon on a previous photo of the moon, using the same lens & camera. The only previous photo was the last lunar eclipse. The supermoon actually was slightly bigger. No-one experiments anymore. They just photograph it with no interest in a science experiment to see for themselves a size difference with their own camera, from the same location.
Posted by Jack Crossfire | Aug 10, 2014 @ 06:44 PM | 1,932 Views
Google & Yahoo jumped on the email encryption bandwagon last year, then prompty got a lot more aggressive about turning over anyone who stored any suspicious content on their account. Google's mane victory was a pedophile who was arrested after a content ID algorithm applied to all gmail content found naked kid photos in his account.

After the pedophile was arrested, Google went on a renewed campaign advertizing complete "end to end" encryption between it & Yahoo's servers. Their email service was not only as private as a hard drive, but so was Yahoo's.

Is the hype about email encryption just a modern dragnet that's trying to leverage ignorance to get criminals, or is there hope for someday having a completely private link between 2 points? Technically, private webmail email is impossible.

The message has to be encrypted in the sender's browser using the receiver's public key, then decrypted in the receiver's browser. The decryption can't happen anywhere besides the receiver's browser. Wherever the receiver wants to run a different browser, the private key has to be entered in the browser & it has to be decrypted in the new browser.

The key pair is usually a hash of the password or something that can be changed. If the user changes keys, every email has to be downloaded from the server, decrypted with the old keypair, reencrypted with the new keypair, & uploaded again. It's completely impractical if the user has 1 gig of stored emails & 1 gig of online storage was originally what sold gmail.

At most, the "end to end" encryption being advertized can only encrypt the transfer over the wire. It has to be decrypted on the final server that dispatches it to the reader.
Posted by Jack Crossfire | Aug 10, 2014 @ 01:02 AM | 2,558 Views
So skype finally pulled the plug & required everyone to upgrade their 2010 binaries. They got rid of the static binaries & the ALSA support. It now requires 64 libraries, which must all be tracked down, manely the complete 32bit Qt set. Mercifully, it still runs on 2010 era ld-linux.so.

After 20 years of audio problems, the final solution to audio configuration is now considered to be pulseaudio. Skype also no longer retains your password unless explicitly forced by a hidden button.

Sound configuration previously required creating a .asoundrc file with a bunch of routes & some carefully calculated buffer sizes. It automatically worked. The new procedure requires 1st running pulseaudio, then running pavucontrol, then setting the input source in Mix2005 to Rear mic & setting a monitoring level, then manually unmuting the output & input devices in pavucontrol, manually setting the levels pavucontrol can see, then finally running skype.

Pavucontrol can neither store its configuration nor access all the registers. No mixer besides Mix2005 can, so some parameters have to be written by Mix2005 & some have to be written by pavucontrol. Every adjustment to Mix2005 causes pavucontrol to mute again. There's no way to adjust the monitoring level during a call, since that's only available on Mix2005. The current ALSA driver maps the mic to rear mic. Only Mix2005 can access all the registers for monitoring the mic level.

Finally, Skype buffering...Continue Reading
Posted by Jack Crossfire | Aug 09, 2014 @ 01:16 AM | 2,820 Views
So you want a server side script to download an image, scramble it so Sprint can't degrade the quality, & forward it to a client. Simply forwarding the image through https would be ideal, but free hosting of https is extremely rare. There are many free servers with varying amounts of cgi support. Few have been around longer than 5 years, yet they all advertize being around since the dawn of internet time. Their cgi support varies from nothing to just Perl, to Python but no javascript or C. Sourceforge.net allows C but no sockets. x10hosting was the winner, with Python.

Code:
#!/usr/bin/python

import socket
import zlib
import sys
import string

if len(sys.argv) < 2:
	print "Content-type:text/html\n"
	print "Need a URL"
	sys.exit(0)

argArray = string.split(sys.argv[1], '/')

host = argArray[2]
path = "/%s" % (string.join(argArray[3:], '/'))

#print host
#print path
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((host, 80))

s.send("GET %s HTTP/1.1\r\n\
User-Agent: Mozilla/4.0 (compatible; MSIE5.01; Windows NT)\r\n\
Host: %s\r\n\r\n" % (path, host))

buffer = [];
buffer2 = [];
gotLength = 0
length =  0
while 1:
	try:
		fragment = s.recv(0x1000)
		if fragment:
			buffer.append(fragment)
			buffer2 = ''.join(buffer)
			if(gotLength == 0):
				index1 = string.find(buffer2, "Content-Length: ")
				index2 = string.find(buffer2, "\r\n\r\n")
				if(index1 >= 0 and index2 >= 0):
...Continue Reading
Posted by Jack Crossfire | Aug 07, 2014 @ 11:03 PM | 2,090 Views
The quest to remove Commie cast revealed Sprint has a transparent proxy transcode all the jpgs at the network level to reduce the file size. The quality reduction is 75%. The same result happens whether you try a proxy server or your own private server.

It is possible to bypass the processing, using https, but very few servers actually support https. Proxy servers that advertize anonymous browsing don't actually support https or don't support wget.

Looks like timelapse webcam movies are going to be the next victim of the recession. With the amount of outrage over Commie throttling Netflix or Netflix charging penalties to Commie customers, people only get outraged when they're told to & Sprint degrading jpg images is just an area they haven't been told to be outraged over.
Posted by Jack Crossfire | Aug 06, 2014 @ 10:17 PM | 1,841 Views
So there was an interview at a follow cam startup. At 1st sight, the guy made up his mind. There was a courtesy lunch & then what was originally planned as a 5 hour tour was terminated after 1 hour.

They weren't interested in anyone over 30, but there was also a large experience gap. They were all just starting out in UAV design & may have wanted the novel ideas that people with minimal experience give, rather than the clouding of years of bad experiences. They may have wanted absolutely no skepticism that the idea was going to work.

They were way behind the other follow cams. Since everyone relies on the same 3D Robotics load with minor changes, it probably wasn't a big deal to languish. Like most every other idea getting the most funding, it was very unlikely to work. Would still say there is enough time before the sh*t hits the fan for the follow cam startups to make significant progress towards the goal.

It was disappointing that a place with no prototypes, minimal experience, & a very hard idea to realize was able to get significant funding, while the other ventures in toys & video editing were unable to get any funding after many prototypes, massive experience, & despite ideas that were equally feasible.

The interview guy had a PhD in CS from the U of T at Austin. The CEO had an MBA from Stanford. The education is definitely a consistent factor among those who got funded, while the unfunded consistently had very little formal education.
Posted by Jack Crossfire | Aug 06, 2014 @ 12:36 AM | 2,196 Views

After running out of IP addresses, Comca$t disabled all the old routers. After a few days without service, an upgraded router with private subnet appeared. The upgraded router was almost able to saturate the home network, but completely unaffordable. It was surprisingly the same speed as the $100 plan, but they charged only $88.

It was finally time to start experimenting with shutting down the cable guy.



3 megabit plan, for $73 instead of $88. It's manely a test to see if it can be done away with.

...Continue Reading
Posted by Jack Crossfire | Aug 04, 2014 @ 01:12 PM | 1,565 Views

With the growing amount of red on the war map, it's amazing the economy hasn't been affected. The oil keeps flowing & the stock market keeps going up. As long as you don't fly over 1/3 of the world, travel is unimpeded. If conflicts in the last 5 years are all counted, the entire map is red.

It would be convenient if the news provided a summary of all the fighting or referred to it all as "the war", but it's not officially a world war. It can't be officially called "the war" because US's president is completely in over his head.
Posted by Jack Crossfire | Aug 03, 2014 @ 06:55 PM | 1,894 Views
Despite the media focus on code.org, massive spending on CS in primary school, massive expansion for H-1B visas , there's no demand for people who can just program. There is demand for people with formal CS education & massive experience in very specific languages like Hack, Go, & Swift, languages invented by 1 company specifically for 1 application.

It's a new way of doing business. Languages based on industry standards, that could be transferred between many jobs are all but obsolete. Each company now develops their own language, specifically for their needs. Google invented Go. Apple invented Swift. Facebook invented Hack. There may soon be a time when every single application begins with developing a new language.

The key to the 1 language per application model was eliminating the need for every new language to have new libraries for accessing the system. Instead of requiring new libraries, all new languages access the system through HTML. They just communicate to the system through a character stream & might have some libraries for parsing the DOM tree.

A positive sign is while interpreted languages were the rage from 2000-2010, all the new languages are natively assembled again. It's more secure to have the output of a trusted compiler on the development machine sent directly to the hardware on the consumer machine, than rely on an interpreter on the consumer machine which could have been compromised. Developers have famously breached the Dalvik...Continue Reading
Posted by Jack Crossfire | Aug 02, 2014 @ 07:11 PM | 1,866 Views

No, it doesn't work, but it has been willed into working by massive numbers of reposts saying it works. It's a fine example of how very little of the internet is real, from the economic boom to the self driving cars, but has been willed into reality by the number of reposts. People are happy about the illusions, which is probably good enough. Someday we may never need know a day outside a simulated world.


Read about the quantum vacuum plasma thruster years ago & it wasn't any more credible then with an audience of 1 than it is now with an audience of 50 billion. The theory is by bouncing microwaves in a container, some of them move forwards & some move backwards. The mass of the photons in the microwaves creates inertia. Since 1 end reflects fewer microwaves than the other, more photons push in 1 direction & since the waves reflect many times, a single wavelength produces many bounces.


Of course, it does rely on expelling mass like every other engine. The mass of the photons leaked from the end with lower reflection is what propels it forwards. Bouncing the microwaves doesn't increase the thrust, but reduces it. The waveguide isn't 100% efficient, so photons are leaked from both ends. If the entire wave was expelled from 1 end with no reflections, it would be more efficient.

Like a modern dot com applying thousands of megabytes of a multitude of programming languages to print hello world, it's a case of success achieved by extreme overhead & enough complexity to sound convincing. So no. You can't buy a self driving car, there are fewer jobs than there were in 2007, newtonian physics hasn't been broken, but who knows if living in reality is still necessary.
Posted by Jack Crossfire | Aug 01, 2014 @ 08:57 PM | 1,931 Views
Going to Bakersfield would have been a total disaster. Don't think there was ever another time when something more disastrous was about to happen, outside of politicians. There were definitely crooked times & times which felt like they caused disaster, but nothing that extraordinarily, overtly, outright bad. Fortunately, wasn't wrong about marriage.
Posted by Jack Crossfire | Jul 29, 2014 @ 10:59 PM | 1,971 Views
After Orbotics & Anki comes Sifteo. They weren't bought by Google, but it was another play to make a quad copter into an intelligent toy. Intelligent toys are still probably the most viable market for quad copters.

https://www.sifteo.com/home

There are many videos naming the sensors in the Sifteo cubes: acceleration, RFID, & touch screen, but few complete examples of a game being played. There are some home videos with some employees explaining the games, with very little screen footage. As with Goog glass, Goog Tango, & chromecast, the intent is to provide a platform with an assortment of sensors, some industrial design, some really bad marketing, & rely on 3rd parties to program it.

Some game examples:

https://www.youtube.com/channel/UCPF...2qsvCHg/videos

There were 3 seconds of 1 cube being used as a claw to grab objects in 3 other cubes by tapping the claw cube on the other cubes. Some games use each cube as a scrabble game with bigger pieces. There are centipede games where the player has to move the field rather than the centipede. There are some guys who became fascinated with developing for them.

The buyout is of course not about the cubes, but an easy way of getting people with experience designing toys to design a flying toy platform. The Sifteo cubes require a base station, so the indoor quad copter game will probably use a base station for navigation.
Posted by Jack Crossfire | Jul 28, 2014 @ 07:47 PM | 1,900 Views
There was a long time rumor that the Donner party, or at least the leftovers, were buried in Dublin. The rumor was false. Elisha Harlan is buried there, but was only a grandson of George Harlan, who led the 1st wagon train on a harrowing journey through the Hastings cutoff. Various pioneers who made the 1st crossing of Hasting's cutoff in the same season as the Donner party are buried in the valley, but none who actually got stranded in Truckee.

Little was made of Brigham Young using the Hastings cutoff to reach Salt Lake. It was just a footnote in all the literature. Truth be told, it was a big deal. The route was initially proposed by Lansford Hastings, a confirmed con artist. He hoped to create an independent nation in Calif* with him as leader by getting Americans to migrate through this faster route.

In reality, the path through the Wasatch mountains was virtually impassible. The Donner party traversed it just a year before BY & it contributed to their deaths. Kiwipedia tells a harrowing tale of boulders having to be moved, harrowing canyons, brush having to be cleared, wagon wheels having to be locked because of the steep inclines, & only 1.5 miles per day of progress.

BY followed this same ill fated route, was the 1st one to lay eyes on it after the Donner party crossed & perished, but was apparently much better equipped with 143 men instead of 30. His party followed the tracks of the Donner party & benefited greatly...Continue Reading
Posted by Jack Crossfire | Jul 27, 2014 @ 02:49 PM | 1,968 Views
Surprised to find feshmeat.net/freecode.com was shut down. Just like the fever that accompanied the initial start of Gimp & GTK, another piece of the golden age has passed. It was 1 of many bought by VA Linux during that golden age. It & all the other VA Linux assets were eventually bought by dice, "specialized websites for select professional communities". If you got a project on it before it was shut down, you're now immortal.

They claimed a loss of traffic. There's definitely a loss of interest in source code level, freely downloadable PC software. A new generation that would have followed the GPL path has gone to paid mobile apps instead, while the generation that started freshmeat.net has moved on to middle management & families.

The itunes/play system that Apple started was such a revolutionary way of automating software releases & getting paid, there was no way everyone was going to keep going GPL, even on the merits of free source code "benefiting the community". No-one in 1999 thought the evil commercial software industry would find a way to lure developers back out of open source, but convenience & ease of getting paid ended up being the factors that did it.
Posted by Jack Crossfire | Jul 26, 2014 @ 06:45 PM | 1,978 Views
Rope Swing Zipline - NFL Stadium (2 min 38 sec)


Note how the brushless gimbal equipped quad is no longer the center of attention but a transparent tool as normal as a shoe. In just a year, perfectly stable shots from a floating vantage point a few feet from people dangling in mid air that were never seen before are the normal look of video. Part of it was still an illusion because the stadium was empty of anyone it could crash on.

Unfortunately, you can't stay a cool zip lining 20 year old forever, even though no-one ages on the goo tube.