Чем мы дышим? Почему я бы не доверял Яндекс.Погоде, Google и IQAir

Давайте поговорим о воздухе в Хабаровске. Сейчас там серьезная проблема: город занесло дымом от лесных пожаров. Но интересно, какая у нас информация о качестве воздуха?

Free Stuff - December 2023

The December 2023 recipient for the Great Scott Gadgets Free Stuff Program is a STEM Camp where students will have the opportunity to use the requested HackRF One to do a Quantum Physics experiment with laser light and modulated RF. We are excited to see how the experiment goes and to see pictures from the camp!

Ламповый лабораторный источник питания для ламповых устройств

Лабораторный источник питания – практически незаменимый прибор в хозяйстве любого человека, увлекающегося самодельными электронными устройствами. Существует широчайшее разнообразие источников с самыми различными выходными параметрами, но заложенная идея обыкновенно одна – это блок питания, который обеспечивает гальваническую развязку от сети и имеет регулировку выходного напряжения, которая обеспечивается встроенным стабилизатором. Очень часто такие источники питания могут работать ещё и в режиме стабилизации выходного тока. Поскольку я плотно занимаюсь ламповой электроникой, то мои требования к такому прибору несколько специфические, поэтому готовые решения не смогли их удовлетворить. Оставался один вариант – сделать такой прибор самому, о чем и пойдет речь в данной статье.
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An interview with Interaction Designer Arthur Carabott Part II

Part II of an interview with Interaction Designer Arthur Carabott who worked on the Beatbox Pavilion for the 2012 London Olympic Games.

The post An interview with Interaction Designer Arthur Carabott Part II appeared first on Music Hackspace.

Free Stuff - November 2023

The November 2023 recipient for the Great Scott Gadgets Free Stuff Program is Ryan. Ryan works as a wireless systems administrator for a public school. He coaches robotics and programming teams after school. Ryan has asked for a HackRF One to show the students in his clubs how to interact with the wirelss devices around them and to inspire them to explore RF as future career options.

OsmoDevCon 2024: "Using bpftrace to analyze osmocom performance"

I've presented a talk Using bpftrace to analyze osmocom performance as part of the OsmoDevCon 2024 conference on Open Source Mobile Communications.

bpftrace is a utility that uses the Linux kernel tracing infrastructure (and eBPF) in order to provide tracing capabilities within the kernel, like uprobe, kprobe, tracepoints, etc.

bpftrace can help us to analyze the performance of [unmodified] Osmocom programs and quickly provide information like, for example:

Histogram of time spent in a specific system call

Histogram of any argument or return value of any system call

You can find the video recording at https://media.ccc.de/v/osmodevcon2024-203-using-bpftrace-to-analyze-osmocom-performance

OsmoDevCon 2024: "Introduction to XDP, eBPF and AF_XDP"

I've presented a talk Introduction to XDP, eBPF and AF_XDP as part of the OsmoDevCon 2024 conference on Open Source Mobile Communications.

This talk provides a generic introduction to a set of modern Linux kernel technologies:

eBPF (extended Berkeley Packet Filter) is a kind of virtual machine that runs sandboxed programs inside the Linux kernel.

XDP (eXpress Data Path) is a framework for eBPF that enables high-performance programmable packet processing in the Linux kernel

AF_XDP is an address family that is optimized for high-performance packet processing. It allows in-kernel XDP eBPF programs to efficiently pass packets to userspace via memory-mapped ring buffers.

The talk provides a high-level overview....

OsmoDevCon 2024: "GlobalPlatform in USIM and eUICC"

I've presented a talk GlobalPlatform in USIM and eUICC as part of the OsmoDevCon 2024 conference on Open Source Mobile Communications.

The GlobalPlatform Card Specification and its many amendments play a significant role in most real-world USIM/ISIM, and even more so in eUICC.

The talk will try to provide an overview of what GlobalPlatform does in the telecommunications context.

Topics include:

security domains

key loading

card and application life cycle

loading and installation of applications

Secure Channel Protocols SCP02, SCP03

You can find the video recording at https://media.ccc.de/v/osmodevcon2024-173-globalplatform-in-usim-and-euicc

OsmoDevCon 2024: "Detailed workings of OTA for SIM/USIM/eUICC"

I've presented a talk Detailed workings of OTA for SIM/USIM/eUICC as part of the OsmoDevCon 2024 conference on Open Source Mobile Communications.

Everyone knows that OTA (over the air) access to SIM cards exists for decades, and that somehow authenticated APDUs can be sent via SMS.

But let's look at the OTA architecture in more detail:

OTA transport (SCP80) over SMS, USSD, CellBroadcast, CAT-TP, BIP

The new SCP81 transport (HTTPS via TLS-PSK)

how to address individal applications on the card via their TAR

common applications like RFM and RAM

custom applications on the card

OTA in the world of eUICCs

talking to the ECASD

talking to the ISD-R

talking to the ISD-P/MNO-SD or applications...

OsmoDevCon 2024: "Anatomy of the eSIM Profile"

I've presented a talk Anatomy of the eSIM Profile as part of the OsmoDevCon 2024 conference on Open Source Mobile Communications.

In the eSIM universe, eSIM profiles are the virtualised content of a classic USIM (possibly with ISIM, CSIM, applets, etc.).

Let's have a look what an eSIM profile is:

how is the data structured / organized?

what data can be represented in it?

how to handle features provided by eUICC, how can the eSIM profile mandate some of them?

how does personalization of eSIM profiles work?

There is also hands-on navigation through profiles, based on the pySim.esim.saip module.

You can find the video recording at https://media.ccc.de/v/osmodevcon2024-174-anatomy-of-the-esim-profile