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Joined 2 years ago
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Cake day: June 23rd, 2023

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  • The issue with cloud providers like AWS is that they charge for virtually everything, and that makes it easy to rack up charges if you forget about something you spun up as a test last week and forgot to terminate it. For larger companies it can be a significant issue. So there are other companies out there that you can use to scan your entire AWS account, summarize what you’re using, and highlight things you may not need any more. They’ll also recommend cost savings measures like paying for a year of server time up front instead of paying as you go. If you know you’ll need a server for a year then paying annually is a lot less expensive.

    On the plus side, you don’t need to deal with things like hardware failures. We have a large AWS environment where I work, and we’ll occasionally get an email informing us that an instance is “running on degraded hardware”. A simple reboot (power cycle) will move the instance to new hardware. And if you decide you need more RAM, more CPUs etc. then it’s also as simple as rebooting.



  • The ship regularly undergoes maintenance, so it’s constantly checked for things like rot etc. and parts of the hull etc. are replaced as needed. There’s a dry dock at the Navy yard where it’s berthed and every few years the news says it’s being put there for a checkup.

    During the sail my understanding is that the biggest concern was the use of modern materials in the sails & rigging. 200 years ago the sails would have been made of linen, which is fairly porous, so some percentage of wind would pass through it. Modern sails are made from materials based on plastics that catch virtually all the air. So the concern was if they raised all the sails they could introduce far more stress on the rigging & masts than the ship had ever encountered. So out of an abundance of caution they only used some of the sails.

    I also remember hearing that during the planning of the event the Navy wanted to have a couple larger modern ships sail by as part of a salute. That was reportedly shelved when it was pointed out (by somebody not in the Navy) that the wakes of those larger boats were bigger than the Constitution itself.







  • Only some VOIP calls are routed over the internet. Most calls, while digital, are still routed over the proprietary networks owned & operated by the major telcos.

    The internet is a packet switched network, which means data is sent in packets, and it’s possible for packets to end up at their destination out of order. Two packets sent from the same starting point to the destination could theoretically go over completely different routes due to congestion, etc. The destination is responsible for putting the packets back together properly. Packets can also get delayed if other higher priority packets come along. It’s for reasons like these that both voice & video on the internet can occasionally freeze, stutter, etc. Granted the capacity & reliability of the internet has improved greatly over time so these things happen less and less often. But the fact still remains that a packet switched network isn’t optimal for real time communication.

    Telephone networks on the other hand are circuit switched networks. When you are talking to somebody on a telephone then there is a dedicated circuit path between you and the other person. Each piece of the path between the two of you has a hard limit of the number of simultaneous calls it can handle, which ensures it always has the capacity to serve your particular call. If a circuit between two points is maxed out then the telephone exchange may try to route your call via a different path, or you may just end up with a busy signal.

    Packet switched networks also don’t have those hard limits that circuit switched networks do. So packet switched networks can get overwhelmed (think DoS attacks) which can also lead to outages.



  • Spoofing is a whole hell of a lot easier said than done. Content delivery networks like Akamai, Cloudflare, etc. all know exactly how different versions of different browsers present themselves, and will catch the tiniest mistake.

    When a browser requests a web page it sends a series of headers, which identify both itself and the request it’s making. But virtually every browser sends a slightly different set of headers, and in different orders. So Akamai, for example can tell that you are using Chrome solely by what headers are in the request and the order they are in, even if you spoof your User-Agent string to look like Firefox.

    So to successfully spoof a connection you need to decide how you want to present yourself (do I really want them to think I’m using Opera when I’m using Firefox, or do I just want to randomize things to keep them guessing). In the first case you need to be very careful to ensure your browser sends requests that exactly matches how Opera sends them. One header, or even one character out of place can be enough for these companies to recognize you’re spoofing your connection.



  • Wary why? I work remotely in IT and manage a ton of Linux systems with it. Because my company has a large number of remote employees they limit us to Windows or Macs only, and have pretty robust MDM, security, etc. installed on them. Since MacOS is built on top of a unix kernel it’s much more intuitive to manage other unix & linux systems with it.

    Personally I haven’t used Windows really since before Windows 10 came out, and as the family tech support department I managed to switch my wife, parents, brother, and mother in-law all to Mac’s years ago as well.