A New Project
With the start of a new assignment cycle, the time has come to start an open source project. For the 0.3 release of my open source development course, my classmates began brainstorming new ideas for internal projects that we could envision making for the remainder of the course. A friend of mine had several ideas, but one appealed the most to me: An application that used a device’s network card to send data directly to another network card, cutting out the middle-man (without internet, or even LAN). After telling him how much I liked the idea we pitched it to the class.
This DarkChatter was born. In my eyes, the details are still a bit up in the air, however. Would this be a full blown chat application, or just message-in-a-bottle deal? Would it fully anonymous, or somewhat anonymous with persisting identities? Would it be a mobile application, or would the permission issues or required rooting make PC the preferred platform? (edit: it seems that this may be easier for an iPhone but I’m an android user).
I’m still not sure yet where it will go. But in all of this I know where my preference lies. I think I want to be closer to the lower levels on this. What is going on with the hardware, the packets, and what difficulties are there in doing this? Why is this not already a more popular thing? Whether it is a chat app or not is not the biggest factor for me. However, first we need to get this off the ground, and get people on board.
For that reason I consider this a research week. Some of the choices that need to be made must be done by someone who is informed on the topic. As I am not an expert at networking or app development, I want to prime myself on the relevant topics.
Research Begins
The project’s original mastermind pointed me to Scapy first. Scapy is a tool that allows you to craft packets in any way you want, even if it doesn’t seem to make sense. This does seem useful, since we are likely to be doing some non-standard networking wizardry, and this will allow us to customize things to our needs. Though it is based in python, which makes me wonder how to get it running in the context of a larger codebase in another language.
After reading a bit about Ad-hoc Networks and going down the rabbit hole to read about Mesh Networking, I realized that there could have many nodes communicating at once. However, I am probably still against group chatting in the interest of time and reliability. It also got me wondering as to the distance limits and how chaining would work. Could this be extremely useful in areas of high population density? Or would other people be slowing down my device by using me to pass data as a middleman? But, back on topic…
After looking up a list of similar applications, I found that Bridgefy offers an SDK for communicating without Internet for up to 100 ft. It doesn’t however say that it is free, so I am afraid that it is likely not. The silver lining is that if they are able to deliver these services without jail-breaking anything, perhaps we can too. But the lack of existing open source projects in this realm is going to hurt, and require me to do much more research with less hand-holding. Hopefully I won’t be in over my head.
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