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Comment Re:Yeah Right (Score 1) 122

But were those long address protocols designed to be routable in a worldwide network? Sure, Ethernet had a 48-bit address too, but it was only intended to be a unique hardware ID. There is no way to contact an arbitrary Ethernet MAC address outside of your LAN, even if you already know that it exists. Were they designed to work with the low-speed serial links that were common back in the day? Sure, you can spare a few extra bits when you've got over a million per second, but not when you've got a mere thousands of bits per second.

Back in those days communications were slow (56Kbps was about 6 characters per second, or 7cps synchronous). And CPUs weren't fast. People wouldn't have tolerated protocols that took up a significant percentage of CPU time. More importantly, fast routing depends on custom logic to handle headers without a CPU, and variable-length headers make this much harder. IPv6's optional headers are tricky enough, but variable address lengths would have been very hard to process with custom logic.

And encryption? It was literally a non-issue for network protocols back in those days because it is so compute-intensive. The point of a network protocol is to route data, you don't stick something as expensive as encryption on the lower layers without a good reason, such as wireless transmission. WiFi has link-layer encryption, but that disappears once the data goes onto a wire. And if you're not going to encrypt the headers anyhow (how do you use the options that specify encryption in an already encrypted header?), then why the fuck even bother? If the data needs to be encrypted, put that at layer 5 or 6 or 7 of the protocol.

Also, which algorithm? Any sufficiently fast algorithm from those days would be useless today. DES was brand new in the '70s, and eventually got chips, but you're going to require one of those in every network node? There are still unanswered questions about how its specific design was chosen. All specifying an algorithm would do is keep a bad algorithm alive forever. SSL is still trying to shake off bad algorithms. We've already thrown away at least two generations of encryption just for WiFi alone, that you can still use, and it's barely 20 years old. And yes, the munitions bullshit was another reason why they would have kept it completely out of the network protocol. It just isn't the business of a routing protocol to deal with encryption.

Hindsight is easy when you don't consider the limitations of what was knowable or possible back in the day. Very few things (other than perhaps the limitations of classful routing) could have been foreseen in what was still considered a mostly experimental system. There was no way they could have known that TCP/IP (which wasn't even their first protocol!) would have ended up the winner and persisted for decades until long after the point where it had run out of addresses.

Comment Re:48 bit IPs would have been nice (Score 1) 122

48 or 64 bit addresses would have been enough, IPv6 only used 128 bits because its designers wanted to be really, really, really sure that we wouldn't run out, this time, for sure. The initial classful address allocations didn't help, but we eventually reached a point where a single wasted class A only puts off exhaustion by a few months. What broke everything in the end was the sheer enormous number of addresses used by mobile networks. Now we have enough bits that we can use Ethernet MACs as part of routable addresses and still have plenty.

The problem is that back when IP was new, even 56Kbps was considered fast. TCP headers are already 20 bytes. The overhead of 4 more bytes per packet would have been significant, but 12 more bytes per packet? That's 2ms per packet at 56K asynchronous, and 12ms at 9600 bps. PPP had a way to shorten headers for this reason, but it was a later protocol, after the more obvious SLIP had already been in use.

Comment And much of it can be easily blocked by the MTA (Score 1) 45

Apparently due to the need for cheap domain names, spammers are running their outbound mail configured with cheap TLDs. I suppose they are doing this so that they can have an actual domain name that resolves properly because it's too easy to block an invalid domain name?

Whatever the reason, if you run your own inbound MTA, a lot of spam can be blocked by simply setting it to discard any mail from these sleazy TLDs, before even reaching the point of doing blackhole list lookup. The worst ones these days are .top and .stream, because apparently you can get a domain for $0.88/mo. Sure, spam still comes in from pwned computers, but a surprising amount comes in from IPs with properly resolving A records, and a surprising amount of that spam comes from TLDs that no sane person would be sending mail from.

So I guess some good did come out of ICANN getting greedy with selling all those new TLDs after all.

Comment Re: Double your storage by making a hole. (Score 1) 201

All of the computers with "standard" disk controller chips used the index hole. (And some CP/M machines were hard sectored, which definitely requires it. That one time I tried to format a 5 1/4" floppy that I didn't realize was hard-sectored was certainly interesting.) I know the TRS-80 used the index hole (I usually made a rough index hole with an X-acto knife), and Atari used it too (I've seen it in the XF551 code).

The Apple II didn't use the index because Woz found out that he didn't need it (even copy protection just used the relative position timing between tracks), and I don't think Commodore used it either.

Comment Re:AT&T DSL? (Score 1) 43

They started deprecating the old ADSL-1 service four or five years ago, at least in the SBC areas. Proper U-Verse is VDSL-2, but I'm sure there are still plenty of areas which never got the Project Lightspeed (FTTN) upgrades. Also, those upgrades date back to the days when it was still SBC (Southwestern Bell Co.), so it will probably vary based on what the RBOC was doing when acquired.

Comment Re:How will that save bandwidth? (Score 1) 43

They have definitely been pushing DirecTV hard over the past year or so since buying them: a DirecTV flyer in almost every weekly stack of junk mail, plus almost monthly direct mail to existing U-Verse customers, even those with their IPTV service.

I think the main reason to abandon the IPTV has to be that they've finally realized that the last mile bandwidth on crap copper is just too precious to use more than 50% of it to stream TV (and FWIW, they charge $10/mo extra for the privilege of receiving HD, probably to discourage the higher usage), so now that they own DirectTV they'd rather shill that than actually install the fiber that they've been putting off for decades. That's going to bite them in the ass eventually. When they installed U-Verse at my mom's house, the tech had to try a second and a third copper pair to get one that would even work.

Sure, it's technically cool to push video over VDSL2, but it's simply more economical to push one-way content from a satellite. Coax works so well because it's a wideband system, and it's even possible to put a one-way wideband signal on fiber separate along with data, but DSL has a much lower bandwidth limit over a pair of aging copper wires.

Meanwhile, I'm moving from one Google Fiber city where it wouldn't have reached me for years anyhow (far NW Austin), to another (San Antonio) where it also probably won't reach me for years.

Comment Re:So much for being useful for music (Score 1) 495

I wouldn't exactly call the mini headphone jack studio-quality to begin with. You can get USB sound dongles from $10 for a cheap dongle with 3.5mm jacks, to $40 for a 7.1 with multiple headphone jacks, or $40 for a 2-in 4-out DJ unit with RCA plugs, and you can get pro ones with a better better quality ADC/DAC and XLR/TRS jacks for a (big) chunk of change more. Or even a full USB mixer panel.

If you're using a laptop, you probably want a docked set-up for studio work anyhow, and USB means less plugs to connect. On my Late-2011-17", I rarely use headphones just for playing music (this ain't no iPod that you stick in your pocket), but I do have a USB unit (with proper RCA jacks) wired to my home theater audio stuff when I want to hear music on real speakers, and I get amplifier headroom for the bad source levels often found with streaming.

On a laptop, I'd be fine with an extra USB port instead of a headphone jack. I can always plug in a cheap tiny dongle if I need headphone audio. And on a desktop, who cares? I'd probably use optical on a desktop. Looking at the panel space they take up, if they also remove the line-in, that's more than enough for another USB-A port, or maybe even enough for two USB-C ports.

A cell phone is different because there aren't a lot of generic USB ports to slap adapters on. (Cue picture of the Lightning headphone dongle that won't let you charge at the same time.) Also, the headphone jack credit card readers are quite common among nomadic retailers. Perhaps a brick dongle that plugs into Lightning with a credit card slot, headphone jack, and charging port? It could even have a smart card chip reader! Those Square things do seem kind of flimsy to me.

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