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Comment: Re:the more things change... (Score 1) 130

by butlerm (#43364051) Attached to: Rare Docs Show How Apple Created Apple II DOS

The Apple IIgs was dramatically different from all other Apple II models. It was backward compatible, but came with a 16 bit processor (the 65816), much more RAM (256K or more), greatly improved sound and video, and a GUI shell much like that of the Mac, plus color, which nearly all Macs lacked at the time. It was a little underpowered compared to the 68000 based Mac, Amiga, and Atari ST, but a more than respectable upgrade to the Apple II series nonetheless.

As educational / entertainment devices even the older Apple IIs ran circles around the PC until EGA was widely deployed in the late 1980s. PC games inevitably were designed for CGA graphics, with a fixed set of four unimaginative colors at a time. The Apple II was better than that almost ten years earlier, to say nothing of the much less expensive Commodore 64. The PC was intended primarily for business purposes, and it showed.

Comment: Re:35 Days to write an OS (Score 1) 130

by butlerm (#43363617) Attached to: Rare Docs Show How Apple Created Apple II DOS

If you asked the creators, they would probably be embarrassed to call it an operating system at all. Apple DOS didn't handle keyboard support, video support, sound support, or printer support. That was all handled using either the monitor (a BIOS in ROM that was not part of DOS), peripheral card ROMs in some cases, or by direct access to the hardware.

MS-DOS was similar. It handled file I/O and that is it. A disk operating system, not a computer operating system. The BIOS was separate, not controlled by Microsoft, but rather by the PC manufacturer, and in ROM.

Comment: Re:what's happening with SCTP? (Score 1) 150

by butlerm (#43257189) Attached to: A 50 Gbps Connection With Multipath TCP

A stateful firewall doesn't need to block transport layer protocols it doesn't understand in order to provide a meaningful level of security. All it needs to do is block packets from IP addresses that corresponding interior address has not recently communicated with, with a reasonable time out. UDP is handled much the same way today.

If the developers of stateful IPv6 firewalls do not ship devices with such a reasonable configuration by default, they will block the deployment of new transport protocols indefinitely - at least all those that do not resort to the awkward expedient of running on top of UDP.

Blocking new transport protocols developers can reasonably handle with a standard policy is bad for efficiency, power consumption, latency, user experience, and so on in the long run - TCP is far from ideal as a transport protocol goes. In a number of ways it is outright backwards. If you want to impede the long term development of the Internet, degrading the end-to-end principle unnecessarily is a good place to start.

Comment: Re:what's happening with SCTP? (Score 5, Informative) 150

by butlerm (#43255145) Attached to: A 50 Gbps Connection With Multipath TCP

Work is underway for concurrent multipath transfer for SCTP as well. Also known as CMT-SCTP. There are significant challenges in doing this sort of thing though. SCTP wasn't designed for CMT, and probably needs much more radical changes than the current architects are proposing to do it well.

Changes like subflows with independent sequence numbers and congestion windows, to start with. SCTP is much further ahead in the connection handling and security department, but MPTCP has the odd advantage of resorting to independent subflows to begin with, and if it can handle path failure properly, it might well be ahead in the CMT game, if byte stream semantics are all you need.

Comment: Re:what's happening with SCTP? (Score 4, Informative) 150

by butlerm (#43255017) Attached to: A 50 Gbps Connection With Multipath TCP

On the contrary, SCTP is a transport protocol just like TCP, except with a large number of added features. The main problem with SCTP has nothing to do with SCTP at all. It is that NAT devices do not support any transport protocol that they haven't been programmed for in advance. This makes SCTP next to impossible to deploy on a broad scale - NAT, that wart upon router-kind, is ubiquitous.

TCP would have exactly the same problem if it were a new protocol. A NAT device requires relatively deep knowledge of TCP to support it at all. It play games with both ports and addresses, keeps track of connection state, and so on. Ordinary routers do no such thing. A NAT device is a transport layer proxy by another name.

Comment: Re:It worked better with relays (Score 1) 202

by butlerm (#42678285) Attached to: Multi-State AT&T U-Verse Outage Enters Third Day

No, he said that the government breaking up the monopoly was "criminal"

I guess that is why one should quote a line or two of the comment he or she is responding to. The one you were actually responding to was hidden.

And when I say "simple engineering", I mean standard engineering practice. No one in his right mind designs a mission critical system for tens of thousands of people without full redundancy and usually automatic failover as well. A system that size that goes down for more than five minutes is more likely to be the result of engineering malpractice than anything else.

I still have a traditional land line, because it is reliable. I can't remember ever picking it the phone up and not having a dial tone. That would most definitely not be the case with any other kind of service available to residences and small businesses. The PSTN was designed to be reliable, and the people who designed readily available Internet access service designed it by the same standards that one might use for toys. Entertainment devices.

No one cares very much if they can't watch I Love Lucy for a couple of hours, although every television station I am aware of is about three orders of magnitude more reliable than the DSL / cable monopolies as well, if not quite as reliable as the PSTN.

Comment: Re:It worked better with relays (Score 1) 202

by butlerm (#42677603) Attached to: Multi-State AT&T U-Verse Outage Enters Third Day

That is quite the red herring there. Did the poster say we should restore the AT&T monopoly? No. What he said (in so many words) is that the systems were engineered to such high standards that they never went down.

The suggestion that we would have to return to monopoly pricing in order for Internet access providers to give reliable service is preposterous. It takes some simple engineering is all. Which the current folks at AT&T (formerly Southeastern Bell) are apparently either incapable of or are prevented from doing. The folks at Comcast and CenturyLink are similar.

If these quasi-monopoly providers can't deliver basic service that doesn't take large areas down for hours on end, they are inviting government regulation to make them engineer their systems so they don't. Not price regulation, engineering standards regulation.

Personally, I appreciate it when I cross a bridge and it doesn't collapse under the offered weight. That doesn't seem to be a particularly high priority at most of the monster ISPs these days - quite the opposite. Lets make the most unreliable service we can get away with seems to be the order of the day.

Comment: Re:pci-e X8 is limmted IO why not at least X16? (Score 1) 72

by butlerm (#42654185) Attached to: Will "Group Hug" Commoditize the Hardware Market?

This is intended for server use. No video output required. The PCIe part is actually optional. I wouldn't expect to see this in workstations anytime soon, not without a major redesign at any rate. The form factor is designed for small, low power processors. The interface is not designed for SMP or anything like that either.

Comment: Re:This would be awesome.. (Score 1) 72

by butlerm (#42654073) Attached to: Will "Group Hug" Commoditize the Hardware Market?

Basically, they are sawing the motherboard in 2, where the CPU and memory are on the daugterboard, and the rest of the components (SATA,USB3, PCIe slots, sound, video outputs) are all that remain on the motherboard

It is actually a micro-server architecture. Think small form-factor blade servers with an optional PCIe interconnect, optional remote SATA devices, and one mandatory ethernet interface, all running through what looks like an ordinary PCIe slot, but isn't.
http://www.opencompute.org/wp/wp-content/uploads/2013/01/Open_Compute_Project_Micro-Server_Card_Specification_v0.5.pdf

Thus spake the master programmer: "Time for you to leave." -- Geoffrey James, "The Tao of Programming"

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