Review: Sigma BC 16.16 STS CAD cycling computer

▼ As I wrote earlier: recently, I lost another bike computer so I needed a new one. I decided to get a more recent version of the Sigma BC line that I've been using for the past decade: the Sigma BC 16.16 STS CAD. These seem to be on the way out now, being sold out almost everywhere. But no obvious replacement that isn't more expensive and more complex, so I'm glad I got to get one of the last ones.

The first 16 (roughly) indicates the number of functions. The second 16 is, as far as I can tell, the platform year: 2016. STS is the digital wireless communication system that allows the "computer" to talk to two different bike speed sensor as well as a cadence sensor. The speed sensor sits on the bike's front fork where a magnet on a wheel spoke tells the sensors how fast the wheel is turning. The cadence sensor does the same for your pedals. I got the package that includes a speed sensor and a cadence (CAD) sensor. You can also get just the speed sensor. Or get an extra speed sensor for a second bike.

How it works

I actually did use my previous Sigma BC with two different bikes, and that worked very well. You need to tell one of the sensors to be on the second channel. You then get to set different wheel diameters for the first and second bikes. This is important, as the computer needs to know that wheel diameter / circumference to determine how fast you're going and how much distance you're covering. (In my case it was always 28" / 2200 mm.)

The Sigma sits in a little holder. You twist it to release it so you can take it indoors if you leave your bike outside, that way it won't get stolen. My previous Sigma BC 9.16 STS wouldn't necessarily sit very secure in its holder, hence me losing it. For the 16.16 this seems less of a problem: you really have to put in some effort to make it click into place. It's also not compatible with most earlier cradles. The default way to secure the holder is with a rubber band. But with a couple of tie wraps the holder is locked down more tightly. I reused my previous speed sensor and an older cadence sensor that I still had lying around.

So what do you get out of the BC 16.16 when cycling?

First of all, the current speed is displayed at all times. The whole kilometer per hour numbers are displayed prominently, with fractions of a km/h shown with a much smaller single digit. This part of the display, which also has some status icons, such as connectivity and first/second speed sensor, use a segmented LCD. However, the lower part of the relatively tall display is a pixel LCD. This shows all kinds of information, such as:

• Trip distance
• Average cadence
• Cadence
• Ride time
• Fuel save
• ETA distance / time / clock

Some of these are not so interesting, but you can't turn them off.

The device maintains both statistics and totals. Statistics are numbers of kilometers and hours of activity during the current month and past eleven months. Totals are just the totals of the same for as long as you care to keep them running. On my previous BC I kept a running total of the number of kilometers I rode during the year. So I had to reset that number to zero at the beginning of the year. The monthly statistics are updated whenever you reset a trip distance, and roll over at the start of the next month automatically.

The backlight is pretty clever: if you turn it on, you tell the BC a start and end time. Between those times, whenever you push either of the buttons, this will turn on the green backlight for a few seconds. A second press will let you control the device as normal. Outside the configured dark hours, first presses are handled as normal and the backlight doesn't come on.

Not sure what impact all of this will have on battery life. With the old one, I had to replace the CR2032s in the "computer" and the sensors about once a year. You may or many not lose your statistics and/or settings when changing batteries.

ETA counter

One nice new feature over my previous Sigma BC is that this one supports an ETA (estimated time of arrival) counter. You set a distance, start the count down and the BC 16.16 will show you the distance to your goal and either the time to reach it or the clock time when you will reach it. You have to choose between the latter two options. I find the clock time when you are expected to reach your goal more useful. The time estimation seems to work quite well, not immediately jumping all over the place when you've stopped at a traffic light.

NFC

With an Android phone you can use NFC to read data from the BC 16.16 using Sigma's app. Unfortunately, this doesn't work with the iPhone. To some degree this makes sense due to Apple's limitations. But a simple read action to collect some data is still possible. With an NFC reading app I get a URL from the BC 16.16. Obviously that wouldn't be enough to completely sync all data, but it would/should work for reading cycling trip data from the last few days in the form of a URL or other simple data format. But no, iPhone users get nothing here.

Conclusions

I really like how Sigma Sport keeps improving these simple bicycle computers. The ETA feature seems like a good addition, and the most important information is displayed nice and clear. The automatic monthly statistics are a good way to keep track of any goals you've set for yourself. So if you find yourself wondering how fast you're going or how far you've cycled fairly regularly, but you don't want to mess with smartphone apps or complex/expensive GPS-based bike computers, one of these BCs is highly recommended.

Permalink - posted 2023-01-01 - 🇳🇱 Nederlandse versie

Speed and cadence sensors for you bicycle

▼ It happened again: I look at my bicycle handlebars to see how fast I'm going, but my bicycle computer was gone. This happens to me every three to four years. A goot moment to reconsider what information I really need during and after cycling. That would be:

• current distance
• current speed
• total distance per day / week / month

Current distance and speed are mostly relevant during longer rides. I could use my Apple Watch for this. But I don't want to be forced to always use my Apple Watch (and suffer the resulting power use for running the GPS the whole time) to record the total distance for all rides big and small. So for that, I need an extra sensor.

Bike speed sensors measure the revolutions of your wheel. That way they also record the total distance traveled. These days there are speed sensors that use bluetooth low energy (BLE) to transmit your speed/distance to another device. Like your phone. Many of these sensors also support Garmin's ANT+ protocol.

However, it turned out that the apps from makers of two of such sensors require you to create a login on their system. What kind of nonsense is that? The bizarre thing is that apparently these days this is so normal that reviews don't even mention it. Apart from hassle and privacy the problem I have with this is that if the maker discontinues their server, your device no longer works.

It's interesting that several of these sensors don't work with a little magnet on a spoke that the sensor sees flying by, but they're mounted around the hub of the wheel. So apparently they can count the revolutions of the wheel that way. This is of course a bit of a hassle when you need to replace a battery, especially if the sensor is mounted on the back wheel.

So I came back to Sigma Sport. I've had several of their BCs ("bicycle computer"?) over the years. For a long time, I didn't understand their naming convention. But it seems like they use two numbers: the first is the number of functions and the second the year a new platform was released. Currently that's 16 (2016). So the BC 14.16 has 14 functions, including recording elevation changes. The BC 16.16 (which I ordered) has a few more functions, including an ETA timer. That seems useful. (But it doesn't seem to have the elevation sensor.) The BC 23.16 has even more functions, but the screen gets pretty crowded/complex. See Sigma Sport's Youtube channel for more info.

Sigma Sport has bike computers where the sensor is connected to the mount on the handle bars with a wire and also wireless BCs. Those come in two varieties: ATS and STS. ATS is an analog protocol and is less reliable, but probably cheaper. STS is digital and has the advantage that one bike computer can be coupled with both a speed / distance sensor and a cadence sensor, and that for two different bikes. Your total distance is then recorded separately for both bikes. So I would definitely go for an STS model.

With the different models, like for instance the BC 16.16, you can buy the wired variant (just "BC 16.16"), the wireless variant with just a speed sensor ("BC 16.16 STS") or the wireless variant with a cadence sensor included ("BC 16.16 CAD").

Permalink - posted 2022-12-20 - 🇳🇱 Nederlandse versie

Has BGP routing security failed (yet)?

▼ In the thorough style we've come to expect from him, Geoff Huston tries to answer the question Is Secured Routing a Market Failure? Please read about the market aspect (and the limitations imposed on the IETF by big router vendors) in that article. His final conclusion is broader, through:

But mostly it's a failure because it does not deliver. Security solutions that offer only a thin veneer of the appearance of improvement while offering little in the way of improved defence against determined attack are perhaps worse than a placebo.

20 years ago I went to my first IETF meeting and there I learned about S-BGP and soBGP. It would take another almost ten years for RPKI to be standardized and fifteen years for the BGPSEC specification (which is largely S-BGP with the RPKI functionality removed) to be published. RPKI is gaining some traction but hasn't been able to stop at least some determined attackers. There are no production level implementations of BGPSEC after five years.

So why is that? True, if people would be prepared to pay extra for secure routing, we'd have it by now.

But I think the bigger issue is failure to understand the problem.

Looking at the valley-free model, we can observe that the right hand part of the network hierarchy is trusted by the sender of the routing updates / receiver of the packets, while the left hand side is trusted by the receiver of the routing updates / sender of the packets.

This hierarchy is pretty flat, so there's usually only a handful of networks on each side. So telling the world that those are networks you trust should be something we can do reasonably efficiently. Then, the only thing is to make sure that there are no network hops in the path that aren't trusted by either side.

Earlier this year, RFC 9234 "Route Leak Prevention and Detection Using Roles in UPDATE and OPEN Messages" was published. This adds some information to BGP that lets it detect paths that aren't valley-free. The nice thing about this mechanism is that it protects two networks that implement the mechanism against mistakes made by networks that don't implement the mechanism.

We still need better mechanisms to thwart determined, purposeful attackers, but the good news is that we've made life a lot harder for those already. So even though we're not there yet when it comes to secured routing, it's not so much that we've failed, but that we are taking too much time to succeed.

Permalink - posted 2022-12-13