Stuff Yaron Finds Interesting

As part of developing Thali we have a series of stories. One of our stories is -1 whose goal is to enable the native discovery and high bandwidth P2P frameworks we have on iOS and Android to successfully work with JXCore’s implementation of Node.js on those platforms. We originally had intended to start with story 0 but we have had enough challenges at the native layer that it made sense for us to just break out a simpler story using TCP/IP sockets rather than the full PouchDB stack as our first baby step. This article explains the simplification.

As part of the Thali project we are working on using BLE and Wi-Fi Direct to provide for local discovery. That is, the ability to discover who is around you using BLE/Bluetooth/Wi-Fi. This feature has enormous implications for people’s fundamental rights to privacy as well as personal security. So in this article I try to enumerate what rights I believe users of local presence software must have for such software to be considered ethical. I built these rights based on Kim Cameron’s Laws of Identity.

As part of Thali we are trying to enable people to easily build peer to peer apps on mobile devices using PouchDB. A problem we have run into is how to implement ACLs in a way that doesn’t cause developers writing on our platform to tear their hair out. I make a proposal below but I have to admit that I have no idea if it’s right or sensible. But I figure we have to start some place. What do you think? You can share your ideas on this blog or better yet, on Thali's mailing list!

Awhile back I ran an analysis to pick a backlog manager for Thali. My winner was Pivotal Tracker and I really like it. It’s super slick. But as an open source project we need to run our backlog out of our GitHub issues so we can manage everything in one place. While Pivotal Tracker has an add-on that provides GitHub issues integration, it’s clearly an afterthought. So I’m back to look at backlog managers that run straight out of GitHub. My winner this time is Waffle

Asking about a system’s performance is usually an invitation to a fight, not to useful data. But I did want some idea of how JXCore, a fork of node.js that runs on mobile OS’s, performed on iOS and Android. See here for more info on JXCore. Since the work I’m doing heavily involves PouchDB I decided to take the PouchDB performance tests and run them in six different environments and compare the results. Over all, one should expect node.js on a modern phone (Android or iOS) to be around 10x slower than on a PC. Which honestly, isn’t that bad when you think about it. I want to give a shout out to Brian Lambert for making the iOS tests happen and to Oguz Bastemur from Nubisa for helping us past various bugs. Oguz was very patient with Brian and I and we really appreciate it.

JXCore is a fork of Node.js that introduces multi-threading support and a Javascript engine abstraction layer to plug in different Javascript engines. They have support for iOS using Spidermonkey and Android using v8 and Spidermonkey. Below I provide a FAQ about who they are and what they can do.

In Thali identities are public keys. But typing in a 4 Kb RSA key or even a 512 bit EC key isn’t exactly easy. So how do users securely exchange their keys? Our original approach was using QRCodes. But lining up the phones, scanning the values, etc. is all a serious pain. So if ultimate security isn’t a requirement our backup plan is to use a variant of Bluetooth’s secure simple pairing with numeric comparison which itself is just an implementation of a coin-flip or commitment protocol. The main downside of this approach is that it provides a 1:1,000,000 chance of an attack succeeding.

[Updated on 3/9/2015 with a new appendix, the last two questions at the end are new.]