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Although most of the time my schedule is fairly predictable, every couple days I'll shift things around and come home from the pool (or directly from work) at a different time of the evening. This, unfortunately, prevents me from creating an accurate program on my thermostat to manage the HVAC system in my condo.
I've been searching around for a decent Wi-Fi thermostat for awhile, now. I'd like to be able to control the heating and air conditioning remotely. My requirements appear simple, but apparently they're not:
I can't find anything that meets even half of these requirements!
The best I've seen so far both look really nice and sport some good features, but require management of the thermostat via a web interface running on the manufacturer's servers. Yeah, this means that all the thermostat does is create an outgoing connection to some external server and wait to receive commands. Become a statistic and give some external party access to the HVAC system and current temperature of my condo? No thanks! I want something that I can manage directly via my local network (or VPN).
So, right off the bat, these get bumped from the list:
Some of the above (I'm looking at YOU, Carrier!) even charge a recurring fee for access to the web portal functionality. Despicable!
Any ideas? Am I going to have to build my own with a microcontroller?
I had a chance to try out one of the new Sierra Wireless IntelliGo mobile Wi-Fi hotspots from Road Runner Mobile, today. The Wi-Fi hotspot is actually just a little router with WiMAX, CDMA (EV-DO), and Wi-Fi radios. The WiMAX radio represents one of the two so-called 4G cellular technologies, the other being LTE.
The Road Runner Mobile service provided by Time Warner Cable is actually Clearwire's WiMAX service, which falls back to Sprint's EV-DO network (3G) when WiMAX isn't available. It might fall back to 1xRTT, too, if 3G isn't available, but I had no easy way of testing this (well, without driving deep into South Carolina).
To set the stage, I can currently get around 2.7Mbps (megabits per second) with 79ms of varying latency on AT&T's UMTS network on a very good day.
For testing, I used wget to this URL and ran MTR to dax.
I first tried powering up this thing in my condo, and after what seemed like over 90 seconds of staring at the bootup logo, it started up.. but on Sprint's EV-DO network (at 80% signal strength)! I ran my tests anyway, and peaked around 1.3Mbps but averaging around 640Kbps. Latency sucked:
HOST: six Loss% Snt Last Avg Best Wrst StDev 1. foobarz.lan 0.0% 8 1.7 2.7 1.5 10.2 3.0 2. 68.28.249.69 0.0% 8 124.7 264.0 124.7 463.1 127.0 3. 68.28.249.91 0.0% 8 135.8 258.7 127.8 451.9 117.1 4. 68.28.251.54 0.0% 8 154.9 265.8 147.8 455.1 121.1 5. 68.28.255.9 0.0% 8 173.9 262.9 135.3 449.9 118.2 6. ??? 100.0 8 0.0 0.0 0.0 0.0 0.0 7. 68.28.253.69 0.0% 8 134.1 236.0 124.6 419.1 107.7 8. sl-crs3-fw-0-1-3-0.sprintlin 0.0% 8 169.0 229.2 122.0 383.1 85.1 9. sl-crs1-fw-0-7-0-0.sprintlin 0.0% 8 141.2 228.7 125.8 379.7 101.2 10. sl-st21-dal-1-0-0.sprintlink 0.0% 8 128.4 236.8 128.4 377.6 94.6 11. dls-bb1-link.telia.net 0.0% 8 132.3 214.7 129.1 319.1 72.3 12. atl-bb1-link.telia.net 0.0% 8 229.4 256.4 170.0 447.0 87.0 13. ash-bb1-link.telia.net 0.0% 8 240.5 272.1 173.7 449.7 109.7 14. voxel-ic-129445-ash-bb1.c.te 12.5% 8 192.0 259.2 167.7 418.9 104.3 15. 0.te6-2.tsr1.ewr1.us.voxel.n 12.5% 8 176.8 276.4 165.7 525.4 124.9 16. 842.te1-7.csr2.lga6.us.voxel 12.5% 8 168.0 297.1 168.0 607.8 145.9 17. dax.prolixium.com 12.5% 8 203.5 277.2 181.6 558.1 132.8
I had to toggle the option in the web interface to force the unit to only use 4G service. Only after I did this, it barely got a WiMAX signal and got me online. The web interface indicated I had poor signal strength at -88dBm (it rated this at 10% - I guess this is why it automatically picked 3G initially), and I agreed. I could only get roughly 360Kbps and the latency was all over the place:
HOST: six Loss% Snt Last Avg Best Wrst StDev 1. foobarz.lan 0.0% 8 1.6 2.1 1.6 3.1 0.5 2. 71-23-64-2.clt.clearwire-wmx 12.5% 8 276.1 190.1 87.4 485.0 144.0 3. 71-22-7-161.clt.clearwire-wm 0.0% 8 211.2 289.6 111.3 703.8 216.9 4. 66-192-62-1.static.twtelecom 12.5% 8 85.4 316.1 85.4 673.8 225.5 5. ash1-pr1-ge-2-0-0-1.us.twtel 0.0% 8 265.2 266.7 95.9 574.1 183.7 6. 0.te6-2.tsr1.ewr1.us.voxel.n 0.0% 8 155.2 231.1 81.1 474.5 126.4 7. 842.te1-7.csr2.lga6.us.voxel 0.0% 8 125.2 200.7 125.2 374.8 79.8 8. dax.prolixium.com 0.0% 8 124.6 167.3 98.2 297.7 76.1
DNS is slightly intercepted on the IntelliGo, since the PTR record for 192.168.0.1 was translated to $my_ssid.lan. No, foobarz is not my real SSID.
After driving around Ballantyne a little bit, I managed to figure out which tower was providing the WiMAX coverage for the area. It ended up being the one near Toringdon that's easily seen from I-485. I got the signal strength up to -47dBm (80%) by sitting in a parking lot of one of the office buildings in the area:
I could have gotten closer by walking across the grass, but I figured the orientation of the antennas would result in worse signal strength as I got closer. Oh, maybe I was just lazy.
I managed to peak at 6.76Mbps down, while the transfer rate typically hovered around 5.5Mbps. Latency was a little better, too:
HOST: six Loss% Snt Last Avg Best Wrst StDev 1. foobarz.lan 0.0% 8 1.7 6.0 1.7 18.2 7.3 2. 71-23-64-2.clt.clearwire-wmx 0.0% 8 66.1 78.1 65.3 94.4 12.4 3. 71-22-7-161.clt.clearwire-wm 0.0% 8 76.0 77.1 61.1 97.6 12.2 4. 66-192-62-1.static.twtelecom 12.5% 8 65.8 69.7 50.9 92.2 12.1 5. ash1-pr1-ge-2-0-0-1.us.twtel 0.0% 8 80.7 84.3 79.8 97.2 5.5 6. 0.te6-2.tsr1.ewr1.us.voxel.n 0.0% 8 85.6 90.7 74.8 107.6 10.0 7. 842.te1-7.csr2.lga6.us.voxel 12.5% 8 60.7 82.5 60.7 102.9 17.0 8. dax.prolixium.com 0.0% 8 86.5 92.7 82.1 105.9 9.9
Although not shown above, I managed to get one response back from the second hop (the other end of the PPP connection, no doubt) in 40ms. Supposedly LTE's RTT is in the 30s, so this certainly comes close!
Stopping at different points around Ballantyne with an average of around -57dBm got me between 3-4Mbps. Not too bad, but not that big of a jump over AT&T in the middle of the night (ie, no iPhone users).
The IntelliGo device itself is slightly disappointing. Battery life on the unit dropped to around 50% after 50 minutes of moderate use. The startup time before even starting the initialization of the radios is way too long (I mentioned 90 seconds earlier, but it could have been longer). Also, I don't know if it's just a result of the high frequency used by WiMAX (>2GHz) compared to other mobile networks or a problem with the IntelliGo itself, but I was disconnected left & right when driving and moving around. The kicker was hearing a beep (it makes certain noises for connecting & disconnecting from the mobile network, and when clients connect) consistently when I drove under overpasses!
In conclusion, I probably wouldn't buy one of these, but I don't travel too much, either. It's probably great for Internet access at airports and other public places where Wi-Fi is either not free or terribly congested.. as long as you've got WiMAX coverage, which doesn't seem to be too widespread, yet. Sprint's 3G isn't too shabby, though, but still pales in comparison to the speeds and latency of AT&T's UMTS network, even when congested with iPhones.
Well, I still claim to know little or nothing about DNSSEC, but I managed to sign one of my zones, tengigabitethernet.com., and add it to the DLV registry, this evening.
Visualization is here.
Once I write some scripts to automate the rotating of my ZSKs, I'll sign the rest of my zones.
Recently, I described my experience of transitioning from a line of Nokia phones to the Nexus One. One thing that I tried initially, and failed at, was to create some custom wallpaper. I think I've figured it out, although through a hacky sort of solution.
The Nexus One has a display size of 800x480 (HxW) pixels. This resolution is fairly high for a device of its size, which is good, considering its strange two subpixel PenTile display. The wallpaper on Android is usually quite a bit larger than the single display, since the wallpaper scrolls left & right as the user scrolls between different screens. According to specifications, the wallpaper for the N1 should be 960x800.
I created some wallpaper with 960x800 dimensions, and tried it out. However, Android kept prompting me to select a subset of the image and display that as wallpaper (ie, cropping). I tried this out, and got a slightly resampled image, which looked terrible. Wanting wallpaper that wasn't resized on the phone, I looked around, and learned that it's necessary to create an image with larger dimensions than either the screen or wallpaper specifications indicate.
After trying a few things, it turns out that an image of 1600x1200 with actual centered 960x800 content is the sweet spot. Let me illustrate:
I took the beautiful Funchal Bay scene by Ruben Freitas and resize & cropped it to 960x800. Then I expanded the canvas to 1600x1200, while keeping the original image intact. When uploaded to the phone, the crop box by default encompassed the original 960x800 image exactly.
I'm sure there's a better way of doing this, but this works for me!
Also, happy Independence Day!
This is starting to annoy me.
There are a few intersections in the Charlotte area that often present confusion to some drivers. I'll go over two examples that I encounter every single weekday (I am the lime vehicles), and then recount a situation I encountered today.
Consider Ballantyne Commons intersecting with John J. Delaney / Durant Blvd:
The lime and cyan vehicles both start out having green lights. The NC driver's manual (grab it here) indicates that the lime vehicle should turn into the left lane, and the cyan vehicle should stay in the right lane close to the right edge of the road (page 51). This is the way I drive, and this is the way most people drive.
Unfortunately, sometimes you'll see the lime vehicle pause in the middle of the intersection, waiting for the stream of cyan vehicles to stop before turning left. This is annoying, jams up the intersection, and causes pain and anguish for drivers who know the light is typically very short. When I'm the lime vehicle behind another, erm, lime vehicle stopping in the middle of the intersection, I will blow the horn at them.
Sometimes, the cyan vehicles will turn right into the left lane of Ballantyne Commons Pky, causing a potential collision with the lime vehicles. If I'm the lime vehicle, I will blow the horn at these vehicles, too.
Note that if Ballantyne Commons Pky only had one lane in each direction, the cyan traffic would have the right of way, and the lime traffic would have no choice but to hang out in the intersection.
I've only had to do this a few times in this intersection.
Onto another intersection with identical properties, the I-277 offramp intersecting with E Stonewall St:
Here we have the same thing. Both the lime and cyan traffic both have the green light. Lime traffic should turn into the left lane of E Stonewall St and the cyan traffic should turn into the right lane. In this intersection, the cyan traffic does actually have two options, the yellow line is a right turn only lane. Both the right turn only lane and right lane are acceptable paths. This is described in the same section of the driver's manual.
One thing that makes this intersection different than the prior one is the traffic volume. There is hardly any lime traffic volume (usually, I am the only one in the left-turn lane) but there is a steady stream of cyan traffic (this is around 17:25 on a weekday). The light is still pretty short, though. Again, I'll blow my horn at lime traffic in front of me that doesn't move, and cyan traffic that veers into the left lane of E Stonewall St.
Ok, having set the stage, here's what I encountered today (2nd intersection). Heading to MCAC, I found myself behind another vehicle turning left on E Stonewall St, and I noticed that this guy was waiting for the (cyan) traffic to stop before he turned left. He wasn't moving at all, so I gave him a beep or two. He didn't move at all, and, well, I got around him (ok, probably not the best thing to do, but not relevant to the discussion at hand!).
Turns out he was headed to the same destination, and confronted me once inside the aquatic center if I was the "guy in the silver Acura that shot past him." Yep, that was me. He asked why I beeped him and took such action. After realizing he wasn't going to beat me up (ok, he was driving a big white Ford pick-up truck - I suppose I wouldn't have felt that way if he had been driving a medium-sized sedan, but whatever), I told him I've had some bad experiences with folks sitting in the middle of the intersection and not budging, alluding to the fact that the light didn't stay green forever. He then said he didn't turn left because he was worried the oncoming (cyan) traffic turning left was going to go into the left lane, which none did as he was waiting in the intersection. Although it came out rather strangely, I conveyed to him that it was certainly legal to turn left into the left lane, and that the oncoming traffic should stick to the right lane. He then asked me if there was a sign somewhere in the intersection that stated this! I don't recall what I said to that, but ended up apologizing (why did I do that? I am hating myself for doing it!) and we went our separate ways. He did mention this was the first time he drove through the particular intersection, so I suppose it's not bad to be cautious, but still.
So, hopefully this guy won't make the same mistake twice. Either that, or he will just avoid the intersection…
On that note, sometimes I feel the need to carry around the driver's manual in my glove box. You never know when it'll come in handy!
I was poking around on my N1 today, and stumbled across an application, aptly named Antennas, that lists and plots active cellular sites in the area. Surprisingly enough, here's what AT&T looks like from my condominium in Ballantyne:
I always thought I was connected to a cellular site hosted on some power lines by the Ballantyne Hotel, but I guess that's not AT&T's. I'm apparently connected to one in the woods behind my development:
I wonder if it's nailed to a tree, or something. Well, I guess that's not allowed.
I've finally done it. I've washed my hands of Nokia for good. I recently picked up a Nexus One and only looked back once or twice. I figured this deserves a blog entry…
I've owned several Nokia E-series Symbian-based phones since March of 2007. I've used all of them on AT&T's network in the United States:
(yes, I would sell each previous phone on eBay for roughly half the price I paid, except for the E72.. read on to find out why)
The E61 and E61i were good phones. Maybe they were a little slow (speaking both about CPU and the data service delivered by the EDGE technology) in comparison with other things, but they were stable. There were no screen transitions, no frills, and the eMail client worked well. The QWERTY keyboard was large, and the screen was easy on the eyes, not to mention being easily viewable in direct sunlight.
The problems started with the E71, even though the hardware was a big step up from the E61[i]. UMTS (3G technology), a faster CPU, and nice 3.2 megapixel camera were the main features of the E71. Unfortunately, Nokia decided it was going to try to soup up Symbian with some extra silly features, including a camera application that was bloated beyond belief and "modes" that were supposed to help switch between personal and work mode. It also was a smaller phone, which didn't really bother me, but made me miss the size of the E61[i]. The phone also had some major bugs, and crashed quite a bit.
I don't know why I upgraded to the E72. Maybe I just wanted the faster HSDPA (10.2 Mbps vs 3.6 in the prior models, even though AT&T only offered ~7 Mbps in certain areas) and the upgraded 5.0 megapixel camera. Well, this phone was a disaster. I'm going to have to resort to a list, here:
For the eMail client, I don't know what Nokia was thinking. It doesn't support IMAP IDLE (although Nokia says that the phone supports push eMail), and reconnecting to check mail takes almost 2-3 minutes, with the eMail application crashing half the time. It's so bloated, and even the simplest of tasks appears to lock up the phone. It looks like the mail client needs tons of optimization, and was designed for a phone with a much bigger screen resolution. For the E72, it was terrible. I actually stopped using the phone to read eMail, as a result. Oh, and one other thing - if the eMail client is allowed to pull all messages from a folder (which is the default for manually-subscribed IMAP folders), it'll consume all available memory, storage, and require a HARD reset to get things back to normal (yup, reboots and deleting of mailbox definitions doesn't fix this).
As a result, the phone was a pain to use. However, it does have some good points:
Ok, maybe not too many.
I mulled over the alternatives (Android handsets, iPhone, and Nokia N900) and determined I wanted to go Android.
I knew the major struggle with this phone was going to be getting over the lack of a QWERTY keyboard. It seems that everything is moving to touchscreens these days, so I figured I should get used to it.
The phone itself is easy to use. It took me a little bit to get over the QWERTY keyboard, which is more difficult to use than the one in the iPhoneOS (erm, iOS). The voice recognition is nice, though, and fairly accurate (you can speak instead of typing, most of the time). The eMail client works (yay!), the browser is quick, and the camera (5.0 megapixel) provides decent quality. The battery life could be better.
The N1 runs Android. Android is a weird operating system. It's based on the Linux kernel, but the userland isn't what one would normally expect from a typical Linux distribution (directory hierarchy, etc.). All applications seem to stay in memory to aid in multi-tasking, and therefore the amount of free memory is quite low under normal circumstances. Android Market is a centralized shop for applications for rooted and non-rooted phones, which I found strange.
The phone runs Android 2.1_update1, and can be unofficially upgraded to 2.2. The T-Mobile N1 has an official upgrade, but the AT&T version does not, at time of this writing.
Instead of unofficially hacking 2.2 onto the N1, I unlocked the bootloaded and loaded CyanogenMod, which is a modified Android 2.1_update1 with extra features like FLAC support, OpenVPN binaries, extra Unix utilities, and is pre-rooted.
I've got OpenVPN running just fine, and am also using Sipdroid VoIP to connect to my Asterisk system. Well, Sipdroid works well over OpenVPN over Wi-Fi, but barely works over AT&T, due to the jitter on HSDPA. I'm sure if I were near a tower at 03:00, it would work fine, too. I blame all the iPhone users during the day..
I settled on QuickSSHd to allow SSH access to the phone, which lets me securely copy stuff off or onto the phone wherever I am. Much easier than plugging in USB and playing with cables. Since CyanogenMod comes with rsync, it makes it even easier.
Tethering via Wi-Fi, Bluetooth, and USB all work great. Tethering via Wi-Fi does drain the battery very quickly (much more quickly than using JokiuSpot on the Nokia E-series phones, strangely enough).
The phone does support IPv6, and it works great over Wi-Fi. I haven't tried any IPv6 tunneling on the phone, yet.
Now, onto the gripes.
There is a huge bug in Android 2.1_update1 that causes the Wi-Fi radio to shut off whenever the screen turns off. There's a "Wi-Fi Sleep Policy" option in the Wi-Fi advanced settings that supposedly allows one to control when Wi-Fi sleeps (never, only with cable connected, when screen turns off) but none of the options make any difference. There appears to be no remedy to this other than just running an application that will not shut off the screen (Wi-Fi Analyzer has an option for this, among others). Obviously this is a complete waste of power, and presents a real problem for N1 owners.
Supposedly Android 2.2 fixes this issue, and CyanogenMod 6.x will be based on 2.2 whenever the source code is released. I'll be waiting for this day!
Other than that, I've only had one other problem with the phone, which happened yesterday. I've been using Open GPS Tracker to plot routes & speed I take through Charlotte. Unfortunately, when I was driving, the phone crashed and went into an endless reboot cycle. Reading online made me think I might have to do a hard reset, but thankfully booting into safe mode then rebooting again fixed it. I was thinking Open GPS Tracker was causing the problem on bootup, but apparently not.
Normally, I would have sold my old Nokia phone on eBay (it's going around $250 at the time of writing) by now, but unfortunately it seems the security code has been changed. I don't remember changing it, and neither the default code (12345) or my old security codes work. Apparently, the only way to reset this is to send the phone back to Nokia so they can hack it, or something. I found this page which detailed a procedure to add a file to the SD card, and boot the phone. Unfortunately, it didn't work.
So, I'm left with a Nokia E72 in great condition, sitting on my shelf. I don't want to sell a phone with a locked security code.. or do I?
Uh, what's going on here?
I'm going to be surprised if I receive this tomorrow.
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