This is a tutorial I can pass out for friends to collect traces of applications’ web requests.
When I was a wee lad I followed Ken Rockwell’s website. I always used to salivate over the more expensive Nikon lenses as I puttered around with my kit lens on the D90, a crappy 70-300mm tele that ended up stolen, and at long last at the end of high school an 80-200mm F2.8 AF-D.
The one lens I was always super excited to try was the 135mm F2 DC. Often called “the” portraiture lens, it’s a relic from the bad old days of film photography in 1990 when men were men and Nikon still made lenses out of metal and used the old style screw autofocus. Continue reading Fun and Focus with the Nikon 135mm F2 DC AF-D
Today’s lesson is on the spoils of my experiments opening 17 credit cards. I always recommend my friends open credit cards due to the lucrative possibilities they entail, including rewards and what amounts to a free ~30 day loan on all purchases. They serve the added bonus of boosting your credit score when used properly to save you money on home or auto loans down the road. This tutorial is targeted to beginner and intermediate credit card aficionados. (Full time credit card churning pros probably know all this already 😉 Continue reading Credit Cards: How they get you and how to game them right back
I’ve now been driving my 2013 Nissan Leaf for about 4 months. A couple of notes:
I lost a bar of battery capacity around 18,000 miles. This puts the car probably near 2.5 years old, and is indicative that the car spent a lot of time in the heat down in Georgia with its previous owner (and likely the previous owner didn’t go out of his way to use the battery in long life mode). The LeafSpy app currently reports battery State-of-Health at 82% with 19,000 miles.
I think one of the more annoying things about EVs is that the range is specified on Day 1, whereas the average range you’ll see as an owner of a leaf for 5 years will be closer to 80-90% of that figure, dipping to 70% at the end of the pack life. This is much more of an issue with an 85 mile range car than with the new 110 mile leaf or a 200+ mile range vehicle.
I got a Wifi OBD dongle and the LeafSpy app, which has enabled me to access detailed statistics about the car including tire pressure, exact State-of-Health of the pack in %, cell balance, pack temperature sensors, etc. It also allowed me to configure the car to unlock when I engaged park instead of waiting until the vehicle was fully shut off (the only problem is that if I absentmindedly shut the car off without putting it in park first, the doors don’t unlock).
On a related note, I have gotten the car into the “Engine Power Limited”/”Turtle” mode now. It engages at 5 GIDs worth of power as reported by the LeafSpy app, though the indicators for capacity inside the car have long since deactivated at that level of charge
I brought the car into the dealership for a voluntary recall relating to some doodad freezing and they appear to have updated the software. Among the changes, I can now shift into drive sooner after turning the car on and the car makes a different jungle noise when starting up (yay).
Overall, I love the car, but as an engineer there are a few points about it that really irk me.
The car’s handling of power versus accelerator and brake movements is designed with the first and foremost goal of making people who used to drive automatic transmission ICE vehicles feel at home. I understand why this was done, at least in the primary Drive mode. It applies a bit of regenerative braking to make the car feel like an ICE car when you take your foot off the gas, it creeps forward when you remove your foot from the break.
Nissan also introduced a “B” or increased regenerative braking mode. I really love this mode because it allows you to operate the car most of the time without having to use the brake pedal. However, this mode is still engineered to make drivers of automatic transmission ICE cars feel at home rather than trying to make the mode work as it should.
If I’m going 60 MPH and I release the accelerator in B mode, it will apply maximum (30 kW) regenerative braking. However, as soon as the car hits 45 MPH it starts to inexplicably reduce the amount of regenerative braking that it applies, all the way down to around 8 MPH where the car stops applying regen and will instead apply power to the wheels to keep it coasting forward. It’s obvious that if I whale on the brake pedal that it can apply 30 kW of regen all the way down to below 10 MPH, but instead of applying maximum regenerative braking in the regen mode, the engineers instead opted to still require you to press the brake pedal to get maximum regen. Even more frustrating is that the car won’t apply max regen unless you brake quite hard with the standard pads. This also makes no sense: the EV should prioritize regen — no brake pads should be applied until 100% of regen is in use. This increases the efficiency of the drivetrain and reduces wear and tear on the car.
Recommendation: Provide a settings menu to configure the handling of the car in D and B mode. I want to be able to disable the creep in both modes, use D mode to apply no regenerative braking at all when the accelerator is lifted off the floor. I want to use B mode to apply 100% regen available at all speeds so that I can slow the car to a stop without touching the brake. Bonus points for either retooling the brake pedal to engage maximum regen before using the mechanical brakes or providing a separate control that can be used to apply only regen.
Gas vehicles indicate tank capacity by a gauge, which makes sense because it is measuring a level of liquid sloshing around a tank. The EV, in comparison, has the cool capability to tell you nearly exactly how much energy is in the battery down to the Watt Hour.
So the Leaf can tell your exact efficiency in Miles/kWH and it knows the amount of kWH in the battery at all times yet the 2011/12 Leafs literally gave only 12 rough “bars” to indicate available charge and the “guess-o-meter,” that thing you have in your gas car that roughly estimates miles till empty and is usually relegated to the back page of some dash menu.
Leaf owners quickly discovered that the car would tell you exact battery charge through the OBD port and hacked meters to display the real number onto their console with duct tape. In the 2013 Leaf, Nissan, equipped with all the wonders of modern technology, provided an entirely arbitrary percent scale into the dash menu, leaving the near-useless guess-o-meter displayed prominently, and 1/3 of the heads up display dominated by the worlds most useless “tree meter” which literally illuminates a small forest as you drive to make you feel good about yourself.
Here’s why this is terrible: the guess-o-meter basically assumes you will be driving the same exact way for the entire trip. If you drive half the trip on a state route at 40 mph and half the route on an interstate traveling 70, the guess-o-meter will reliably be off in its estimate in both directions because it will assume that the rest of the trip is to be made during the same conditions under which you start out.
Even more infuriating, in the spirit of “fog of war” the leaf stops telling you how much power it has left when it gets down to 5% remaining charge in the battery pack. The only way to know at this point is to plug in a duct tape OBD meter.
Recommendation: provide a meter for kWH in the battery pack, ideally either replacing the guess-o-meter or the tree meter or at a minimum in a software update for all previous leafs. Bonus points if it’s configurable (the user can select %, kWH, or guess-o-meter next to the bars).
You cannot open the charge port while the car is on. Rather than allowing me to pull up to a charger, plug in the charger, and have that action disable the drivetrain, the leaf requires me to shut off the vehicle before charging. Only after charging I may turn the vehicle back on in a “Drivetrain disabled” mode which allows me to use the climate control and radio. It’s really annoying, especially since an entirely electric software-driven car there is absolutely no reason why this isn’t feasible.
The entertainment system feels like I’ve reentered the dark ages. Honestly it’s better to make cars that can slip in Android tablets into the dash than make these archaic resistive touch screens that display blocky unscrollable and confusing menus. For instance: the leaf has a spare SD card slot. You’d think that you could load music onto that spare SD card and play them through the entertainment system, but you’d be wrong. Further, the entertainment system can only read MP3 files off any USB attached storage. How difficult could it be to implement FLAC support?
Quick charging is great, however there are no Quick Chargers convenient to getting from Boston to Portland. With a single quick charge off I-95 north in New Hampshire, this would be easily doable. Without one, I’ll be required to drink beers at a brewery while I wait for my car to charge outside for two hours.
This story chronicles my recent frustration with Comcast Business Internet, primarily due to their lack of clarity on how they provide their service when included with Static IP Addresses.
I decided (probably foolishly, but I have no regrets) to lease my own office “for my company” on Massachusetts Ave in Cambridge as part of my plan to dominate the world and keep all my projects and geek toys in a separate location to my regular apartment. The space is two rooms, a front room and a rear closet, with power and HVAC included at $350/month. (Muahahaha)
So logically I decided to offer to a few of my friends to see if they were interested in sharing the space/hosting a server there. My friend Ross, of course, took the bait and soon I had leased a beautiful man cave, furnished it, and the time came to order business internet.
Nope. Not available. Tried begging. Not happening.
We even tossed in the possibility of running a microwave bridge from a location with FiOS to the office. Still a possibility but we’re in the basement. Will require more thought, and probably a location that costs more than $350/month.
It was to be, sadly, our only option. But I’ve had good results with Comcast in the past. I simply separate church and state: I buy my own modem, I use my own router and handle everything from the point that DOCSIS ends forward. I assumed I’d be able to do the same with the business class service…wrong. My one complaint has always been the terrible upload speed, and I knew I’d be running servers where upload is the more important side of the two.
So I filled out a quote and was shortly contacted by a rep from Comcast’s Business Sales Team or whatever who got me set up with an acceptable plan (75/10). I told him I wanted static IPs and he said that would be fine. He also managed to upsell me on a $5/month TV add on that would give me a few channels to the man cave but also give me a $300 prepaid incentive card. I took the bait (mostly because this is a tax free way to get equity out of the company).
The first signs of trouble
I got the whole 2 year contract I had to sign (which was scary, but he said both that we can scale the service down and stay within the terms or we can get out of the contract if we move to a place in which the service isn’t available). The grand total with the “Business Gateway” was $156/month.
The contract listed 5 Static IPs and “Business WiFi.” (!)
First of all, WiFi (as the term) has sort of been embraced by Comcast as a term that can be trumpeted and sold to customers. Everyone understands what WiFi is…at least sort of. They no longer sell you “Internet” or “IPv4 connectivity,” they sell you “WiFi.”
But WiFi is a bridge of layer 2 ethernet that allows computers to connect without cables. That term is used primarily when describing your services to technological idiots. It’s the same as selling a computer based upon heavy marketing of the peripherals. So why was it listed on a business contract as some service that they were rendering?
Any network technician can spot the confusion: where does the “WiFi” fit into 5 static IP addresses? Getting just Business Internet with Static IP addresses gives you this vision that your setup will be literally a bridge and a layer 2 subnet of IP addresses. No DHCP, no local router, no nothing. WRONG!
The “Business Private WiFi” basically tells you that a whole host of garbage that I thought I was going to take care of myself was included: the router, switch, access point. And from personal experience with the consumer equivalent, the “Comcast WiFi Gateways” are the network engineer’s worst nightmare. They suck, they crash, they perform intermittently so as to inspire the wrath of even the frat brothers who don’t understand that it’s causing the problem, they don’t support local DNS properly, and you can’t even disable the WiFi without calling customer support (just to name a few of the problems).
Basically “Nick’s principle of why you ought not to use DOCSIS Router McWiFi access points” is that any time you start combining devices like that, the performance suffers. The target market shifts lower in the technological IQ range, and they cut corners. For example, Ubiquiti makes a line of exceedingly high performance routers for under $100, and cheap wall-mountable WiFi APs for around $50 that can run on astandard but usable 24V PoE. That system runs like a tank, to the point that I will not install or service non-Ubiquiti systems for my family and other engagements. The amount of times various cheap Amazon ARM router + access points have given me inexplicable trouble is very high. I’ve never had a real dedicated router crap out (except when I misconfigure the firewall to not accept any TCP connections).
So I asked the sales rep and got a nonanswer: but I was told that once I had the service I could “work with the customer care representatives to transfer my static IP addresses onto my own hardware.”
That statement was patently false. I called up another support technician that likewise claimed the exact same thing. They’re both wrong. A Comcast Business customer desiring static IP addresses must lease this “Business Gateway,” because the only supported configuration is to locate the customer’s router within that gateway. They do not support a bridged configuration where you may bring your own router and connect it to a standard DOCSIS modem.
Confused? Read on.
The Comcast Setup
You’re going to laugh when you hear this.
They came in and set up this “Business Gateway.” A few fun facts:
- WiFi is already set up. Yipee.
- By default, you’re now running an Xfinity WiFi Hotspot. Surprise!
- Any computer plugged into the ethernet ports or connected to the WiFi gets DHCPed a RFC1918 “NAT” IP in the 10.1.10.0/24 subnet.
- There’s a firewall with lots of options. Which is confusing because NAT doesn’t need a firewall to begin with because it’s impossible to route into a NAT. The firewall also has settings which clearly refer to the real Static IPs.
- Setting reverse DNS requires contacting support, but is possible!
- Comcast refers to your real IPs as “true static IPs” because they assume nobody knows what RFC1918 is.
- The whole thing is basically undocumented, except for a PDF that refers to an old business gateway from 2006 with different configuration options.
Where are the static IPs? How do I connect to them?
What is the mysterious setup?
Basically, the Business Gateway acts as a router. It is the gateway for your static IP subnet, and is placed at the top of your static IP subnet. We have a /29 subnet, which means that we have 5 usable IPv4 addresses and a 6th that is assigned to our gateway. We can use this 6th address by setting up a IPv4 DMZ, the same disastrous setup that home server operators have been dealing with for eons. To use any static address (once the firewall is disabled in the Business Gateway for “true static IP addresses”), all one needs to do is manually set the IP, subnet, and gateway on your computer and it will route. Easy as that.
Now here’s where it gets funky: it is also a standard NAT router. The same layer 2 network also has a DHCP server which will issue NAT addresses. So by default, any computer connected with DHCP enabled gets a NAT address.
So the not-so-obvious pro of this situation is that you can have two addresses assigned to a computer:
- Primary public and static IP (configured as default gateway)
- Secondary internal static IP (just local traffic)
Both on the same interface. Both will route, allowing you to contact LAN devices and but maintain a primary external IP on the same computer.
To confuse you further, there’s a setting which allows you to “Map” external IP addresses to internal NAT addresses. That’s cool I guess, but it’s very unclear what’s going on or even that the aforementioned configuration is a possibility.
What’s the problem?
First, I’m stuck leasing a hellbox. They didn’t bother to even invent a more sane configuration.
Second, any yahoo who manages to get access to your WiFi network can just change their IP settings and start using your external IPs as their own.
Third, while this configuration may be advantageous to some, it’s not, by any standards, a standard networking setup. Nowhere is this clearly laid out in any of the documentation. And their technicians and phone support haven’t the faintest clue how to explain to you that you’re running a bastardized IP network (much less much else about networking…but they do seem to enjoy using tremendously untechnical terms and conflating the word modem and router constantly).
What’s the solution?
Comcast points out, and rightfully so, that if you disable the DHCP server and WiFi you basically have what they “sold you.” But you’re still stuck leasing the hellbox, and the hellbox is still running a NAT router underneath the hood. Maybe that’s fine, I still don’t like it.
Granted, I cannot compare this to business-class FiOS because I’ve never owned it.
I think what this basically means is that Comcast Business service should really be branded Comcast’s “really small business service for those without any technical expertise.” This setup pretty clearly implies that that’s what they were going for. And to an extent they probably succeeded.
Realistically, I would be a hell of a lot more satisfied if there existed “Comcast’s Technical Guide to Static IP for Business Service” which explained everything detailed in this article and was provided along with the literature when I originally signed the contract. I would prefer if their technicians were entirely educated about this more advanced service, because they clearly aren’t (basically every time I call I can get half a dozen false answers to these simple questions).
Earlier this summer while I was toiling away in Seattle, I asked my dad a crazy question:
What would you say to car sharing a Nissan Leaf and your Passat?
Needless to say that was the beginning of a very slippery slope. By mid-August when I returned we had visited a used car dealership in southern MA to take a look at our options. We decided that this was to be a year long experiment. Continue reading World, meet Fergus! My 2013 Nissan Leaf SV
A few weeks back I wrote about some common nutritional fallacies I’ve heard. A few real world examples have reminded me of a few more, so I’ll list those here: Continue reading Nick’s List of Nutritional Fallacies, Part 2
Anyone who has started to read into some of the controversies of nutrition will quickly find that there’s a lot we don’t know. Answering questions that appear to be trivial can end up taking 40 years and costing billions of dollars… and somehow we still don’t have an answer. Why?
A trivial example: If you take fat out of your diet by cutting out one hamburger, you may have added extra veggies or chicken or candy to your diet. Suddenly, simply determining what happens when you remove one serving of red meat from your diet becomes a multivariate matrix of macronutrients, micronutrients, fiber, and other strange considerations. And then you can repeat this for every feasible item in the grocery store and realize how futile your quest to answer simple dietary questions has become.
Beyond the universal understanding that “less processed is more better” we are left without a lot of understanding about nutrition, and for good reason: it is impossible to say definitively whether a vegan diet is more healthful overall than a ketogenic diet or vice versa.
Nevertheless, there are some basic considerations to which we can apply fairly straightforward logic. What follows are just a few of the examples of false nutritional hypotheses and general stupidity that I will address in kind. Continue reading Nick’s List of Nutritional Fallacies
I’m going to take a brief detour from my usual rants and raves to blast an opinionated rant and rave about a another non-technical subject that I am under-qualified to discuss 🙂
The topic of food and dieting is very big in the old USA (no pun intended). There’s an epidemic of epic proportions, with the percentage of overweight population in the US reaching 75%, and a lot of interesting research about the causes, effects, and issues at hand.
I’m going to share a summary of my research and thoughts on the subject as part of my plan to “get fit” this semester. I’ve switched to a low carb, high fat diet over the past 5 weeks or so and I’d like to share my findings. Take it with a grain of salt (hah) but definitely read on. Continue reading What do I eat today? A discussion of food.
A while back (during construction of my new house), I wrote an article about the capabilities of the DSC 1832 alarm panel. Well, time got the better of us and I wasn’t able to wire the house myself. Instead, we had a third party alarm company provide “a la carte” wiring service. This included (all 22/4):
- Phone line to the outside utility area
- Front + Side door
- 4 motion detectors
- “Basement” wire (which I used for freeze)
- Siren Wire