TCP and UDP have ports. These are 16 bit; there are 65535 or so per IP address. These protocols don't care to differentiate between the ports. Elsewhere, IANA presumes to operate a process to allocate "well-known" ports in the range 1-1023, "registered ports" in the range 1024-49151, and to reserve the remainder, 49152–65535, for "ephemeral" ports. The caller end has to have a port, which is how replies get back within the virtual connection, and these are conventionally picked from the ephemeral range by the OS's networking stack. The whole idea of ports is ridiculous, because it allows ISPs to arse around presuming to decide which services they will "not allow". Anything that allows IPSs to do anything other than shift opaque packets will allow ISPs to meddle and break things, and due to the Law of Meddling, if they can, they will. I am currently working around an issue with Claro, a pretend ISP, blocking port 5060, allocated to SI...
Taleb observed in Antifragile that it took 6000 years between the invention of the wheel, and someone putting wheels on luggage. Sadly, castors without brakes result in a lot of rolling around. This is getting worse each year, as the luggagetards seem to take unbounded delight in reducing the friction in their castors, but never add brakes. Thousands of people are going round announcing they "work in luggage design", but not a single one has implemented the most obvious and beneficial "innovation" available to them. I have so far been unable to (spot test and) buy any luggage with brakes on the wheels, despite asking in several luggage shops. Searching online yields promises of "universal" castor parts with brakes, where "you must have a strong ability in DIY", meaning: they're not universal, and the fitter may as well be crafting the whole item from scratch. It also brings up a 700 EUR piece of Chinese tat, with no brakes visible in the...
A friend's retail business doesn't take cash any more. At first this seemed odd. He said if you take cash, you have to train staff in it, and they can't do it. I didn't believe him. This is such a basic part of functional numeracy that you can take it for granted, for, say, 98% of the population. Then, these four anecdotes on making change from Autumn 2024. In a restaurant in Guernsey, the bill was 41.xx GBP (service charge had already been added), and I handed over 51.30 (ish) to make the change easier. The chap was taking ages, so I zoned out. When I came to, I realised he was counting out pound notes. The change should have been a tenner plus pennies. I said something, and it became clear he was making change from 50.00 GBP. He escalated to more senior team member, who cottoned on to give a tenner. T In Oxford, in a cafe, I ordered a coffee. 3.45 GBP. I handed over a twenty plus the 45p. She knew to open the till, but beyond this, was completely at a loss. She didn...
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