Walking is great exercise, but it’s good for the mind too: it gives one time to observe and to think. At least that’s what I do on my daily walks, and being me, what I usually observe and think about is the local infrastructure along my route. Recently, I was surprised to see a number of telephone company cabinets lying open next to the sidewalk. Usually when you see an open box, there’s a telephone tech right there, working on the system. But these were wide open and unattended, which I thought was unusual.
I, of course, took the opportunity to check out the contents of these pedestals in detail. Looking at the hundreds of pairs of brightly colored wire all neatly terminated and obviously installed and maintained at great expense, I was left wondering why someone would leave such a valuable asset exposed to the elements. With traditional POTS, or plain old telephone service, on the decline, the world may no longer have much use for the millions of miles of copper cable feeding back to telco central offices (COs) anymore. But there’s got to be something this once-vital infrastructure is still good for, leading me to ask: what’s to be done with the local loop?
Continue reading “Ask Hackaday: With Landline Use In Decline, What’s To Be Done With The Local Loop?”
The Plain Old Telephone Service, or POTS, doesn’t get a lot of love from the average person anymore. Perhaps once in a while a payphone will be of use when a phone battery has died, but by and large many people simply don’t have hardwired phones anymore. However, that doesn’t mean that the old landline can’t be put to good use. As [Felix Vollmer] shows us, it’s still possible to get useful hardware running over the phone line.
The YC-KZ02DN is a simple device which hooks up to a standard phone line. It’s capable of answering calls and responding to commands by switching its various relays on or off. [Felix] wasn’t quite happy with the stock functionality, however. Investigation showed the onboard STC15W202S microcontroller can be repogrammed over serial via an unpopulated header. Thus opened the door to hacking the device.
[Felix]’s alternative firmware has a couple of key features that make it valuable. Longer PINs are supported, decreasing the likelihood that malicious actors can gain access to the system. Additionally, the device is set to restore the last relay state after a power loss event. This makes the device far more useful for situations where it’s important to ensure consistent operation. It’s no use if an intermittent power loss stops your livestock’s water trough from filling, for example.
In this day and age of the Internet of Things, an old school telephony hack warms the cockles of our hearts. We’re suckers for anything that recalls the days of rotary dialing and speaking with the operator, after all.