Bastian Bloessl

The vision for a new GNU Radio runtime is to have a straightforward implementation of distributed SDR systems that make efficient use of the platform and its accelerators. Though there have been many projects over the years to address some of these goals, many aspects are challenging to do in the current GNU Radio runtime.

One year ago, several of us got together at the pre-FOSDEM hackfest and started planning how to "write a GNU Radio runtime that works for humans". Since that time the project has taken several different directions, all aiming to make the core aspects of GNU Radio modular and easier to use by laying a fresh foundation. In this talk, we will overview the current state of the "newsched" project, and where we plan to take it.

Most GNU Radio modules focus on the physical layer and less on creating standard compliant data payloads. In this talk, we'll show how easy it is to combine GNU Radio implementations of WLAN and ZigBee with Scapy, a powerful interactive packet manipulation program. Using Scapy, we can quickly craft our own packets and poke at other stations (e.g., by sending deauths) or fuzzing its network stack (e.g, to test an IoT device).

Most GNU Radio modules focus on the physical layer and less on creating standard compliant data payloads. In this talk, we'll show how easy it is to combine GNU Radio implementations of WLAN and ZigBee with Scapy, a powerful interactive packet manipulation program. Using Scapy, we can quickly craft packets that encapsulate protocols from the whole network stack, including WLAN, ZigBee, and higher layers like IP and TCP. Thanks to GNU Radio's socket interface, we can forward these packets into the flow graph and send them out through our PHY. With this setup, it becomes trivial to broadcast WLAN beacons, deauth WLAN devices, or even fuzz protocols by sending frames with randomized, not necessarily standard compliant data. The latter is possible, since Scapy allows to fill all fields of a protocol header that are not explicitly set with random data. This might trigger all kinds of interesting behavior.

Wireless mobile traffic lights are often used to secure construction sites when roads are partially blocked. Some day, when a pair of them was placed close to our home, I set off to explore how they are working. In this talk, I will describe how I used a cheap RTL-SDR together with GQRX, Inspectrum, and GNU Radio to reverse engineer the modulation and frame format of different types of wireless traffic lights. With some patience, I could also make some sense out of the bits. In particular, I was able to extract the signal state and display it in a web interface, mirroring the traffic light. A closer look at the frame format and the apparent absence of any authentication might leave one with a bit of a worrying impression regarding the security of those systems.

The state of SDR, and free/open SDR in particular, is interesting. In some cases, SDR research and progress has been declared dead, implying that there is nothing left to research or develop. Practical usage of SDR tells a different story, though, and users of SDR products run into all sorts of issues every day.

In this panel, we would like to discuss with the audience what the top issues are that SDR frameworks need to solve in the near future -- be they technical, legal, political or anything else.

What are the top 3 items that the realm of Software Defined Radio needs to figure out? In this panel, we invite some experts as well as the entire audience to discuss this question. We shall discuss technical challenges (if there are any) as well as legal and political challenges. Does free/open software radio have any different questions to tackle? If we were to attend a technical conference in the near future, what would be the most mind-blowing thing we could present? Will there be more, competing frameworks going forward, or will they consolidate? These and many more questions shall be the topic of this year's SDR panel.

The Radio Data System (RDS) is a digital subcarrier on ordinary FM radio broadcasts that is used to convey a bunch of information including station name, time, alternate frequencies, and optionally traffic information with the Traffic Message Channel (TMC) protocol. Given its ubiquity, narrow bandwidth demands, and frequency band, RDS might be a good first digital project for SDR newcomers, extending the 'Hello World' of SDR, i.e., the FM receiver. RDS can be received with very cheap hardware like the RTL-SDR and simple antennas making the technology accessible for everybody.

In this talk, I will give a short introduction in RDS / TMC and present the current state of the GNU Radio RDS project. Besides the receiving part, we will also have a brief look in the transmit side that allows you to create your own small radio station including RDS and TMC messages. The information is hopefully just enough to whet your appetite and helps to get you started.

I will discuss new ideas and application domains of our Open Source IEEE 802.11a/g/p OFDM transceiver for GNU Radio. The transceiver is implemented completely in software without the need for changing the firmware of the FPGA.

For that reason, the structure and mode of operation of the transceiver is easy to understand and it is straightforward to extend. In our opinion, an SDR based WiFi transceiver has several interesting applications, one of them being its use for research in Vehicular Ad Hoc Networks (VANETs). In this field, the applications for an SDR implementation range from investigation of security and privacy issues, through simulative performance evaluation of receive algorithms, to experiments in field tests. In the talk, we discuss the possibilities and limitations of the SDR platform, as well as our current state of the art. We will highlight what is already possible, present results of our performance studies, and also show where improvements, hopefully with the help of people from the Open Source community, would be desirable.