Showing posts with label Failover. Show all posts
Showing posts with label Failover. Show all posts

Saturday, May 2, 2020

Building a hardware watchdog timer for a kiosk or other system that needs to run 24x7

It was proven by Alan Turing back in 1936 that the halting problem applies for computing in general, and our contemporary computing machines are no exception.

Would predicting the crashing of an algorithm or program be a possible function, and we would be able to know the edge cases that cause an application to fail or enter a loop, without having to explore the actual scenarios to find these edge cases. To put it simply we would only have to ask the algorithm in which conditions it would enter a loop or end unexpectedly, and by not providing these inputs we would with absolute certainty not enter these scenarios.

Sunday, October 20, 2019

Consumer grade WiFi gear - when fixing the root cause is not at reach

Some time ago, I had to improve the performance and coverage of my home network, so as to be able to use the several devices around the house flawlessly, regardless of the location. Some of these devices have a certain demand for consistent bandwidth, as is the case of the SmartTV for watching IPTV and Netflix, and others such as the smartphones and tablets.

As always I tend to be frugal with spending money in hardware, trying to go with what performs well and is just about enough for the job.

This led me to aim for WiFi gear that would both be somewhat popular and low cost, while at the same time having some hope of being hackable and reflashed to OpenWRT in the future. This was the reasoning when I decided to buy a couple of TP-LINK TL-WR841N routers (with v9 hardware at the time).

At first I set these up and played with the stock firmware, configuring one to play the roles of  NAT, DHCP, DNS, firewall and so on, and the other to act solely as a WDS repeater, allowing WiFi coverage to be extended to the rest of the house.