Efficient Graph Search
Welcome to Drill Bits, a new column about programming. This inaugural episode shows how graph search algorithms can avoid unnecessary work. A simple modification to classic breadth-first search improves the lower bound on its running time: Whereas classic BFS always requires time proportional to the number of vertices plus the number of edges, the improved "Efficient BFS" sometimes runs in time proportional to the number of vertices alone. Both asymptotic analysis and experiments show that Efficient BFS can be much faster than classic BFS. All software used in the experiments is available for download, and suggestions for further explorations are provided.
Security Analysis of SMS as a Second Factor of Authentication:
The challenges of multifactor authentication based on SMS, including cellular security deficiencies, SS7 exploits, and SIM swapping
Despite their popularity and ease of use, SMS-based authentication tokens are arguably one of the least secure forms of two-factor authentication. This does not imply, however, that it is an invalid method for securing an online account. The current security landscape is very different from that of two decades ago. Regardless of the critical nature of an online account or the individual who owns it, using a second form of authentication should always be the default option, regardless of the method chosen. In the wake of a large number of leaks and other intrusions, there are many username and password combinations out there in the wrong hands that make password spraying attacks cheap and easy to accomplish.
Removing Kode:
Dead functions and dead features
Removing dead code from systems is one of KV's favorite koding pastimes because there is nothing quite like that feeling you get when you get rid of something you know wasn't being used. Code removal is like cleaning house, only sometimes you clean house with a flame thrower, which, honestly, is very satisfying. Since you're using a version-control system (you had better be using a VCS!), it's very easy to remove code without worry. If you ever need the code you removed, you can retrieve it from the VCS at will.
The Identity in Everyone's Pocket:
Keeping users secure through their smartphones
Newer phones use security features in many different ways and combinations. As with any security technology, however, using a feature incorrectly can create a false sense of security. As such, many app developers and service providers today do not use any of the secure identity-management facilities that modern phones offer. For those of you who fall into this camp, this article is meant to leave you with ideas about how to bring a hardware-backed and biometrics-based concept of user identity into your ecosystem.
Out-of-this-World Additive Manufacturing:
From thingamabobs to rockets, 3D printing takes many forms.
Popular culture uses the term 3D printing as a synonym for additive manufacturing processes. In 2010, the American Society for Testing and Materials group came up with a set of standards to classify additive manufacturing processes into seven categories. Each process uses different materials and machine technology, which affects the use cases and applications, as well as the economics. I went down a rabbit hole researching the various processes in my hunt to buy the best 3D printer. In this article I will share a bit of what I learned about each process, as well as some of the more interesting use cases I found along the way.
The Die is Cast:
Hardware Security is Not Assured
The future of hardware security will evolve with hardware. As packaging advances and focus moves to beyond Moore's law technologies, hardware security experts will need to keep ahead of changing security paradigms, including system and process vulnerabilities. Research focused on quantum hacking is emblematic of the translation of principles of security on the physical attack plane for emerging communications and computing technologies. Perhaps the commercial market will evolve such that the GAO will run a study on compromised quantum technologies in the not-too-distant future.