You don't even need to go so far as to sniff traffic on any interface. Most linux distros have either lldpd or lldapad built in which gives a bit higher-level interface to the raw LLDP data on the wire. The BSDs also have it. Bi-directional so info can be updated switch-side too. I've used it in combination with other tools, DHCP and whatnot to do something similar to what she wrote about, have individual machines 'know' where they are in a cabinet or facility and change functionality based on that. Works great!
I suspect this referring to a recent post on jwz's blog about his digital signage solution for his nightclub, which spawned a lot of discussion on the comment (click through to the blog post itself):
This assumes your paranoid network admins don't disable CDP/LLDP one day because of nebulous "security reasons" and sabotage your scripts, but this is the wrong time and place to rant about that :)
I sit with a pile of raspberry Pis I throw into different rooms about the house and want to stick assorted tasks on them. My open question was how can I just image them, plug them in and centrally configure what runs on them with no more sd card or Mac detection shenanigans when I change their job.
Somewhat related, years ago I worked in an office that switched to hot-desking, and I spent a while trying to figure out whether was there was a way to automatically generate a map of who was in the office, and whereabouts. Identifying an individual laptop is okay, but figuring out which docking station the laptop was plugged into was a lot trickier without admin access to network hardware (which I def didn't have). This approach may have allowed an individual laptop to figure out where it was, and then update a central location database.
How fun, I solved a similar problem in a similar way. 90 identical devices, each with their own Ethernet cable and 128 Ethernet ports. The solution was to configure the switch to make DHCP assignments based on port number, then the device could just query its own IP address. Port 1 -> 192.168.1.101, 99 -> 192...199
What switches enterprise or consumer tend to support this LLDP? My guess is maybe almost none on the consumer side. I.e. Netgear, to link. Cisco probably does. How about ubiquti?
I know mikrotik supports this. On the higher end, most of the Dells switches I interacted with as well as Aruba had LLDP. Different manufacturers tend to report their interfaces slightly differently though
But also, I was wondering if she was going to say, "these devices have cameras on them which are not used because they are pointed in random directions depending on how they are mounted". And then I was hoping to see an interesting image recognition task, "given this blurry, dim, random image, choose which location it probably came from".
You don't even need to go so far as to sniff traffic on any interface. Most linux distros have either lldpd or lldapad built in which gives a bit higher-level interface to the raw LLDP data on the wire. The BSDs also have it. Bi-directional so info can be updated switch-side too. I've used it in combination with other tools, DHCP and whatnot to do something similar to what she wrote about, have individual machines 'know' where they are in a cabinet or facility and change functionality based on that. Works great!
I suspect this referring to a recent post on jwz's blog about his digital signage solution for his nightclub, which spawned a lot of discussion on the comment (click through to the blog post itself):
https://mastodon.social/@jwz/113209773692118053
(intentionally linked via Mastadon because he doesn't appreciate direct links from HN)
This assumes your paranoid network admins don't disable CDP/LLDP one day because of nebulous "security reasons" and sabotage your scripts, but this is the wrong time and place to rant about that :)
Cool hack!
This couldn’t have been better timed for me.
I sit with a pile of raspberry Pis I throw into different rooms about the house and want to stick assorted tasks on them. My open question was how can I just image them, plug them in and centrally configure what runs on them with no more sd card or Mac detection shenanigans when I change their job.
I’ll be giving this a try!
If lldp proves inconvenient, pi's also have a unique cpu-id, which can be found in /proc/cpuinfo
I think something similar exists on most processors
Very interesting!
Somewhat related, years ago I worked in an office that switched to hot-desking, and I spent a while trying to figure out whether was there was a way to automatically generate a map of who was in the office, and whereabouts. Identifying an individual laptop is okay, but figuring out which docking station the laptop was plugged into was a lot trickier without admin access to network hardware (which I def didn't have). This approach may have allowed an individual laptop to figure out where it was, and then update a central location database.
How fun, I solved a similar problem in a similar way. 90 identical devices, each with their own Ethernet cable and 128 Ethernet ports. The solution was to configure the switch to make DHCP assignments based on port number, then the device could just query its own IP address. Port 1 -> 192.168.1.101, 99 -> 192...199
What switches enterprise or consumer tend to support this LLDP? My guess is maybe almost none on the consumer side. I.e. Netgear, to link. Cisco probably does. How about ubiquti?
I know mikrotik supports this. On the higher end, most of the Dells switches I interacted with as well as Aruba had LLDP. Different manufacturers tend to report their interfaces slightly differently though
Used Arista 7124 and 7150s are pretty cheap on Ebay.
Almost any managed switch will support it. Netgear does. Ubiquiti definitely does, even their APs do.
anything that can run openwrt
LLDP: this is the way
But also, I was wondering if she was going to say, "these devices have cameras on them which are not used because they are pointed in random directions depending on how they are mounted". And then I was hoping to see an interesting image recognition task, "given this blurry, dim, random image, choose which location it probably came from".
I got nerd sniped to the power of 2.
Same could work with microphones. Every spot of the space would have a different resonant characteristic.
Or microphone+speakers, where every device can self-assign an ID, echo it over speakers, and then everyone triangulates everyone else and themselves.