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Joined 1 year ago
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Cake day: June 21st, 2023

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  • I was born in the 1980s. I remember growing up, I always had the impression that by this time in the 21st century, we’d have figured out some way to break the established laws of physics. Maybe it was because of watching so much sci-fi, but I feel like I’m not alone in this. The media seemed to reflect the same line of thinking. “Back to the Future 2” with its hoverboards and flying cars is now set several years in the past.

    Be it anti-gravity, interstellar travel, teleportation, whatever, I always kind of assumed that by now, we’d at least have a working theory of how we might implement it in the next few decades. I think a lot of that has to do with the start of the “information age.” Computers and the way they could connect us were so revolutionary, it seemed like “magic” to the layperson. More “magic” would only be a few years away, right? If we could fit all this power into a box that sits on your desk, then it wasn’t beyond the scope of reason to think that anything was possible; it’d just take a few more years for us to figure it out, then we’d be planning the first NASA mission to another solar system.

    What I never would have predicted is just how rapidly computer technology would advance. We now have supercomputers in our pockets, powered by CPUs that are well into the realm of nanotechnology and are now starting to run into limitations imposed by quantum physics. As a technological society, we’ve probably progressed farther than I would have ever imagined, just not in the way I expected.



  • I don’t know the statutes offhand; I’m basing this on what I was taught in my CCW class years ago.

    The general idea is that the state sets limited laws on where you can’t carry concealed. Government buildings, etc. These restrictions hold the force of law. For a private property owner, they can certainly say “no guns,” but it has the same legal weight as if they said “no hats.” They can set rules for their property, but those rules don’t magically become law. That’s where trespassing laws come in; if you’re asked to leave, they have the right to ask you to do so.

    Some states do have laws in place stating that “no guns” signs are legally binding, but the signs must meet certain legal criteria as far as wording. Surprisingly, I think Texas is one of these states, but I could be wrong.

    My state is solidly blue, so it does seem strange to me that the laws are written as they are.



  • In some states, these signs don’t even mean that a person can’t carry a concealed weapon into the shopping center. In my state, for instance, assuming you are otherwise able to legally carry a gun (meaning you took a class and aren’t a felon), the list of areas where you can’t legally carry a gun is very limited: Federal buildings, courthouses, etc. If a business has a sign posted stating “no guns allowed,” you can still legally carry your weapon in that business. If an employee sees that you’re armed, they can ask you to leave, and you’re trespassing if you refuse, but nothing legally stops you from carrying a gun into the establishment in the first place.

    As a disclaimer, I’m not arguing this one way or another. I have a license to carry a concealed handgun, in fact. Just sharing information.


  • One day, you’re going to die. Unless you are fortunate enough to die suddenly, you’re going to experience the terror and the pain the comes along with dying. Anyone who cares about you is going to be saddened by your passing.

    None of that would be true if you had never been born. Your parents, every parent, has condemned their children to death and has ensured sadness for anyone who comes to care about them.

    The worst thing my parents did? Not using protection or having an abortion. Conceiving a child is the most selfish act any person can do.



  • It really depends on how far back you want to look.

    If the US was to suddenly stop projecting its interests internationally, then as others have mentioned, then likely the world work become somewhat more socialized. European countries would probably step up and try to keep China in check, but without the US contributing to these efforts, it would cause a significant strain on their military resources.

    If the US was to take an isolationist policy 100 years ago, then there is a good chance that WW2 would have been won by the Axis. The Allied forces likely would have put up a good fight, but I’m not sure they would have emerged victorious against the combined Axis forces. The war in the Pacific would have raged on much longer, and without nuclear weapons, there would have been an extreme loss of life invading Japan. At the very least, WW2 would have lasted much much longer than it did. Depending on the outcome, plenty of countries might currently be speaking German and debating if they should tear down 80-year-old statues of Hitler.



  • This is only true when you have a single transmission medium and a fixed band. Cable internet is a great example; you only have a few MHz of bandwidth to be used for data transmission, in any direction; the rest is used up by TV channels and whatever else. WiFi is also like this; you may have full-duplex communications, but you only have a very small portion of the 2.4Ghz or 5Ghz band that your WiFi router can use.

    Ethernet is not like this. You have two independent transmission lines; each operates in one direction, and each is completely isolated from any other signals outside the transmitter and receiver. If your ethernet hardware negotiates a 10Gb connection, you have 10Gb in one direction and 10Gb in the other. Because the transmission lines are separate, saturating one has absolutely no effect on the other.


  • You are absolutely correct; I phrased that badly. Over any kind of RF link, bandwidth is just bandwidth. I was more referring to modern ethernet standards, all of which assume a separate link for upload and download. As far as I am aware, even bi-directional fiber links still work symmetrically, just different wavelengths over the same fiber.

    If you have a 10GBaseT connection, only using 5Gb in one direction doesn’t give you 15Gb in the other. It’s still 10Gb either way.


  • This is a really good explanation; thank you!

    There is one thing I’m having a hard time understanding, though; I’m going to use my ISP as an example. They primarily serve residential customers and small businesses. They provide VDSL connections, and there isn’t a data center anywhere nearby, so any traffic going over the link to their upstream provider is almost certainly very asymmetrical. Their consumer VDSL service is 40Mb/2Mb, and they own the phone lines (so any restriction on transmit power from the end-user is their own restriction).

    To make the math easy, assume they have 1000 customers, and they’re guaranteeing the full 40Mb even at peak times (this is obviously far from true, but it makes the numbers easy). This means that they have at least a 40Gbit link to their upstream provider. They’re using the full 40Gb on one side of the link, and only 2Gbit on the other. I’ve used plenty of fiber SFP+ modules, and I’ve never seen one that supports any kind of asymmetrical connection.

    With this scenario, I would think that offering their customers a faster uplink would be free money. Yet for whatever reason, they don’t. I’d even be willing to buy whatever enterprise-grade equipment is on the other end of my 40/2 link to get a symmetrical 40/40; still not an option. Bonded DSL, also not an option.

    With so much unused upload bandwidth on the ISP’s part, I would think they’d have some option to upgrade the connection. The only thing I can think is that having to maintain accounts for multiple customers with different service levels costs more than selling some of their unused upload bandwidth.





  • If you’re concerned about power, I don’t see any reason it should matter at all where you have your cameras, as long as your PoE switch is rated to supply your cameras. If your NVR has some kind of built-in PoE switch, then you can probably avoid having a second PoE switch for your cameras by co-locating them in the same network closet, but PoE switches are so cheap, I’d say set it up however it’s most convenient for you. To answer your question of “is it possible,” it absolutely is. I’m doing something similar. I have a lot of cameras, but two of them are PoE and are quite a distance away from my NVR server. They feed into a PoE switch that connects to a second switch that acts as the main switch for the building. That switch has a fiber connection to a third switch that lives in my server rack, and that switch has a DAC connection to my DVR server. They work just as well as the ones plugged directly into my rack switch.

    The only real concern I see is bandwidth. If your cameras and NVR are on the same switch, you’d avoid having to pass the data from the cameras out across your network to the switch that has your NVR. For 4 cameras, though (even at 4k), your total bandwidth is going to be far less than what even a 1GB network can handle. It’s very easy to saturate a switch, though, so this is going to depend largely on your network topology and what you’re using your network for.

    I would highly encourage you to keep your IP cameras on a separate VLAN, though. IP cameras all have a tendency to want to “call home,” and while that might just be for something as simple as checking for firmware updates, I don’t want my cameras connecting to anything outside my network without my permission.


  • Got my two CRS310s, set them up, and they’re working well. I’m amazed with how configurable they are in comparison to my old Zyxel switches.

    I’m not sure I’m setting up VLANs correctly, though. There’s an option to set up VLANS under Interface or Bridge. I have several ports that pass more than one tagged VLAN, and as far as I can tell, that’s only possible on the Bridge. So my Interface -> VLAN setup is completely empty, and my Bridge -> VLAN setup contains all my VLAN assignments.

    I’ve researched this a bit, and it seems like I’m doing it the right way, but I’m a bit concerned I’m passing the VLANs off to the CPU instead of the switch chip. This is the first switch I’ve used with this kind of VLAN setup. Am I on the right track?

    Also, my 1GB SFP modules only work if I disable Autonegotiation; then they show as “Up,” with all the lights on, even if no cable is attached. Not a big deal really, but strange. I don’t have this issue with my 10GB SFP+ modules.



  • I understand what you’re saying. As far as using your school account to sign in to Microsoft Office, the fact that you use a school account should not make a difference in terms of privacy. If you’re using Outlook and Teams for school, just don’t use them for personal things, and you should be fine. If you’re using the web versions through a web browser, then you have nothing at all to worry about. If you actually install the apps, you still likely have nothing to worry about, although I would make sure they’re at least signed out and closed when you’re not using them. You don’t want to accidentally send a message to your school’s Teams group when you’re drunk and watching YouTube videos at 3am.

    As far as “enrolling in your school’s environment,” I’m afraid I don’t know what you mean by that. I know that some companies will install corporate nanny-ware on systems that they issue out to their employees (you’ve probably heard about CrowdStrike), but if you’re using a personal laptop for school, that’s not going to happen unless you hand it over to the school’s IT department and say “please fuck up my computer.”

    Most likely the “cloud” file you see in your documents is a Microsoft OneDrive account that comes included with your school’s Office subscription. You can use it as a backup for schoolwork, ignore it completely, or just uninstall OneDrive. I like keeping my important stuff on local storage, but if you want a place to back up a project, go ahead and use it. Maybe don’t copy your porn stash over to your OneDrive account.

    I am a strong advocate for keeping things separate on your computer. Not necessarily from a privacy standpoint, but more so just to keep everything tidy and easy to manage. If I was just using Teams and Outlook, maybe logging into an online portal, I’d probably just do exactly that without a second thought. If you find that you’re installing a lot of different applications for your studies, like I mentioned before, you might consider setting up a VM. A VM (Virtual Machine) essentially acts as a second computer within your own. You would install a hypervisor (I’d recommend VirtualBox for you), and inside the hypervisor, you can create separate “virtual” computers. You install your operating system, boot up the virtual machine, and use it just like you would a whole separate PC. When you’re done, you shut it down, and when you no longer need it, just delete the VM, and your PC isn’t cluttered with a bunch of stuff you don’t need. The “hard drive” for your VM lives in a single file, and once that file is deleted, it’s as if your virtual machine never existed. One way to think of it is like building a house inside a room in your own house. You still have a bedroom, a kitchen, bathrooms, and a living room. Only in this “virtual” house, you can paint the walls, throw parties, trash the carpet, invite hobos to live on your couch, whatever you want. When the house gets too trashed to live in any more, you just hit “delete” and it disappears; the actual house you live in is still in pristine condition.

    So just as a summary, my opinion is just use your computer normally. Log into whatever school resources you need and don’t worry. If you need to install a whole bunch of school-related stuff that you don’t want cluttering up your PC, set up a VM.

    It’s probably also worth noting that your school almost certainly isn’t trying to damage your computer or catch you doing something you want to keep private. They’re providing resources (a free Office subscription, for example) that they think might help facilitate your studies. You can use those resources, or not, but your computer is still your personal property, and your school isn’t trying to infringe on that.