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Comment Re:What about bandwidth OUT of the concentrator ?? (Score 1) 255

Guarantee? What guarantee? Both DSL and cable internet service are provided on a "best effort" basis. If you want a SLA, you have to pay through the nose for it. Guaranteeing a SLA means the provider has to provision dedicated circuit capacity, instead of letting you complete for channel space on a first-come, first-serve basis.

With DSL, the uplink and downlink depends on the DSLAM-to-CO channel capacity, because DSL is implemented using ATM and virtual circuits in fiber rings. The differing up/down rates are a design decision, based on how many of the sub-carriers are assigned in each direction. Oversubscription is the carrier's choice.

True cable service is another story. The downlink is managed by the head-end, so the feed onto the cable can run at top rate. Yes, the more users who are on the subnet in your neighborhood, the slower things can go. The uplink, however, is a single channel shared by a number of sources, so the upstream channel acts like AloahNet back in the 60s: a fractional load can saturate the uplink because of contention. (ThickNet and ThinNet suffered from the same congestion problem...which is why most people use twisted-pair star networks, even in our homes.)

Comment Re:The law is more specific. Quality voice, graphi (Score 1) 255

POTS is 64 kilobits/s in the ideal case, 56 kilobits/s when the path is digital, about 48 kilobits/s when there are analog diplexing amps and such (which continue to go away, thank goodness). But not let's get caught up in nits...

When you talk about video, you are assuming a single stream of high-quality 1080p video. How many American homes have only one television? (Especially when there is such a glut of analog-only TVs available for a song with the switch to over-the-air digital.) (Or as large-format laptops continue to hit the previously-leased used computer stores.) You can easily have two streams in the poorest of homes, one for the alleged "grown-ups" and one for the kids.

When you start talking about VoIP, you need roughly 100 kilobits/s to handle a single voice conversation and side-channel control, considerably more if you have side-channel "whiteboard" traffic. That's per phone conversation. It adds up when your household has a number of people, and more so in SOHO.

And the cable companies in particular want to keep 1990 pricing as much as they can, because Internet is a cash cow for them when they get CCIEs to maintain the network gear -- an absolute necessity when the cables sell 100/100 fiber to larger businesses.

It's about profit and rate of return. And, unlike the other parts of their business, the rate of return on Internet is (for now) unregulated.

Comment Re:two thoughts (Score 1) 255

3. Not everybody streams HD video. If you don't stream HD video then 25/3 is more than adequate. I watch TV shows from Hulu on my laptop over a 6 Mbps DSL connection.

I don't stream anything, because the short-term packet loss I suffer all the time would clobber streaming. I have "business" cable service, which is fine for mail servers, web browsing, and file transfers, but not VoIP or any real-time applications such as gaming. Skype is just...painful. Even VPN access can be dicey...and that's talking to a 100/100-fibre-connected-through-same-cable-company site.

Instead, I will find DVDs/BluRay at the pawn shops, used-"record" stores, and for things I just can't wait for other people to discard (or movies that people tend to hold onto forever), Amazon and Barnes & Noble.

Comment No need for large bills: Consumers (Score 4, Insightful) 255

"Normal cable companies don't need $100/month for Internet, consumer lobby says.

"The consumer lobby is opposed to a cable industry plan to keep sub-standard Internet server at or above $100/month. Cable companies do just fine with lower rates, the Internet Consumer Association wrote on SlashDot this morning. It wasn't that long ago that Internet access was available for one-fifth the rate, and the cost burden to the cable companies to provide service continues to drop as the Internet access piggy-backs on existing cable infrastructure, especially in the face of cable company promotion of so-called 'triple-play' products: television, telephone, and Internet.

"Notably, no party provides any justification for adopting increased tarriffs for providing service. All the companies provide bogus justifications for charges for service that go well beyond the 'current' and regular' amounts that were in place during the dial-up and DSL days."

(I wonder how the NCTA would respond to such an article, were one such as this parody were ever to appear in print)

Comment Congress is the real problem here (Score 1) 253

Why is the tax code so convoluted that there is an entire industry devoted to following the code? It's because Congress keeps piling on the laws, exceptions, work-around, and "social engineering". Instead of adding law to the US Code, they should be removing pages from the US Code. To make things simpler, start eliminating "targeted" deductions and exemptions/exceptions to deductions, so that individuals and married people can play by the same rules as the businesses, companies, and corporations. If insurance premiums are tax-deductible to one class of taxpayer, it should be the same for all classes of taxpayers.

Completely remove the "negative tax liability". If you are going to give people money, give people money directly, and not via the IRS. The IRS is not a social agency. Their job is to collect taxes. I'm not sure what to do with tax-exempt organizations in the current climate, but the IRS shouldn't be making that determination off their own bat. They should stick to the "revenue" part.

The IRS regulations published in the Code of Federal Regulations (CFR) are to implement the statues passed by Congress. The IRS does not do this off their own bat. Court cases balloons the number of pages of interpretation, because there is no requirement to "backfill" the CFR or the USC, and stare decisis increases the amount of law surrounding tax -- another source of law bloat. That's why WestLaw and Lexus/Nexus is so necessary, and why tax attorneys demand -- and get -- such high fees. Those fees can be chickenfeed compared with the interest and penalties that their clients have to pay out when they don't use an attorney.

I don't have an opinion of the Fair Tax proposal, because I'm not sure I understand it yet. But I do know that there are way too many densely-printed pages in USC Title 26. Shrink that down to something the size of a magazine, and many of the tax ills will be solved. Ordinary people will be able to understand the law they are supposed to follow.

As a consequence, the IRS itself would shrink. And the new IT systems would be far easier and quicker to implement.

(pipe dream, for sure)

Comment Where are the ACCURATE models? (Score 1) 667

I'm coming in late on this. First, the activities of man have released a lot of the sun's energy that has been stored for millions of year. So I agree that the gross heat load on the planet has been increased. Whether this overwhelms our planet's ability to dissipate that heat is open to question. Why is it open to question? Because, without numbers, it isn't science, just an opinion.

The Chicken Little people have been watching with alarm several trends over the years showing varying temperature. First, it's too cold; then, it's too hot. (And the butt of the old Henny Youngman joke: if the water turns black, the baby really needed a bath!) Attempts to model the short-term temperature shift have not accurately predicted what is going to happen in the future. Worse, the models don't accurately reflect the past, when applied to the data collected over the years. How to the CLPs explain this? WIth lame excuses, mostley, that reduce to "we don't know enough".

The research needs to continue. The people who build the models need to add to those models those sources of temperature variations that are just now being discovered, said discoveries having blown the older models out of the water. (pun intended) There are zero-dollar things we can do now to improve the situation. Plant trees, especially re-plant those trees that were clear-cut in the Amazon. Replace incandecant light bulbs (and those mercury-filled CFDs) with LED bulbs, not to save the climate, but to SAVE MONEY in the long term; I'm about 45% through this process myself.

I don't object per se to spending money on the problem. I object to spending money recklessly JUST for climate change, without some accurate way of measuring the effects of the changes. Reducing certain factory emissions results in less acid rain, which can have an adverse effect on buildings, roads, and other infrastructure. Containing the worst methane emissions from oil/gas operations makes perfect sense because we can then use the stuff -- but remember that the release from the Earth without man's help overwhelms our pitiful contribution.

The science is far from settled. If it's truely settled, show me the accurate models that predict, with precision, what we see on November 1, 2016

Comment How do things need to change to live with systemd? (Score 4, Insightful) 551

I fear the day when samba, JBoss, KDE, LibreOffice, GIMP, ... start to be dependent on systemd.

  • * Samba, yes, because it's a daemon.
  • * KDE, yes, because it's a daemon
  • * LibreOffice, no, because as far as I can see it is launched manually. Now, it may need to ask for system resources that may or may not be started at initial boot, but that's a easily partitioned block of code that can see if systemd is there, and run only when it is.
  • * GIMP, no, LibreOffice comment applies
  • * whatever, depends. If it's a daemon, there many need to be something added to the package, but it can be a well-contained block of code that runs once. If it's not a daemon, see the LibreOffice comment.

When I was looking at systemd, one thing I wanted to see in the documentation is how to convert my own home-brew daemons to interface with it properly. Specifically, how to take SysVInit based starts and convert them to use systemd and journald. (Ditto taking UpStart scripts and convert to systemd.) The result needs to work exactly like daemons running under SysVInit. I spent three weeks with CentOS 6 trying to get my daemons to work right under UpStart, and never did get the exact functionality. I had to go back to crontabs for some of the work! So this is not an idle concern to me.

One of the gripes I have is that I want the University of Delaware version of NTP running on my edge boxes. As the group there make tweaks to NTP based on their continuing research, I don't want to wait for another group to do a re-port. That's why I would like to see a published way to interface with systemd/journald that would have minimum impact on the rest of the code base for a daemon.

I can see where daemons need to change. But do they have to be rewritten?

Comment Re:Movies are crap (Score 1) 400

... you might live outside the service footprint of Netflix and Hulu. These include places that can't get cable or DSL, such as rural areas, and countries where Netflix and Hulu have chosen not to operate.

You forgot satellite. But, aside from that, you are talking about people who don't live down the street from a movie house. For these sorts of people, a trip to the movies is only a part of an extended excursion, a day and evening, on the town. Usually, such outings are planned well in advance and anticipated by all in the family (or families). It's not "just a movie" but a broader social experience. One enjoyed at long intervals because of the effort needed to have the outing, and the total cost.

Do you remember your college days? Remember when one of the frats would have regular showings of classic movies within walking distance of the dorms? And the admission fee was enough to cover the cost of the film, the projector, and maybe some money for the frat's pot, but not so rich that you would have to skip eating for a few days? Some of the movies they selected were really bad...but some of them were very, very good. That how I saw Night of the Living Dead for the first time.

In one place I lived, the church high school students would have a "movie afternoon" for the grade-school-age children, showing 16mm prints of G-rated films. Those movies were open to anyone, young or old, who wanted to come. For the older kids, there were PG-13 films, that were acceptable to the church board, shown in the evening (keeping in mind the 9-pm curfew). The crew was all-volunteer, and the church owned the projector and screen, so the admission price only had to cover the rental of the film. On rare occasion, the adult service groups would provide punch and snacks after the film. (not before or during.)

Today, I usually wait until I can get the DVD or Blu-Ray from Amazon for those movies I really want to see, based on the trailers. The rest? I will pick up DVDs from the used-book store, or even pawn shops. So far, for 2015, the only movie I'm considering seeing in the theatre is Pitch Perfect 2, and only if I can see it in a deluxe theatre with a track record of throwing louts out.

Comment Re:35? (Score 1) 376

Just FYI, when someone misspells things at the rate you do (it's "C'est la vie", "breach of contract", "</p>"), I'm not inclined to trust their memory regarding fine detail or attribute credibility to their interpretation of said fine detail.

You might want to introspect about that.

Of course, WTF kind of network admins don't understand about buffering effects on dataflows?

Last question first: those admins who haven't worked with large numbers of TCP-to-serial converters -- I'm talking 6,000 independent datastreams at the same time -- and forget how TCP buffers get filled from a 1000 cps steady-rate source when the converter calculates a RTT of 2 milliseconds over the local network between it and the server. A server running as a guest in VMWare, with no packet aggregation optimization in the host's Ethernet interface. Who never heard of the word "thrashing". Who never saw the guest's real-time clock losing time because of interrupt overload. Who never took a WireShark capture of a connection, to see just how many packets are created for each stream

Criticism on my English and my spelling from an Anonymous Coward? Like that's worth much. Yes, I misspelled some stuff, but that's because what I published was first draft done in a hurry. If it were an article for paid publication, I would have used a real word processor, with a real spell checker, instead of a stupid HTML form. (Free Republic, another forum I occasionally contribute to, does have a decent spell-checker in its contribution entry form.)

And I'll be the first to say that my memory is a photographic one, but the filmbase is made from Swiss Cheese. That's why when I design a system, I use a number of methodologies to minimize the dependence on memory. I tend to design from the top down, then revise from the bottom up. Repeat as needed to nail down the details. I also create use cases: "I'm x and I need to do y," and then I ensure each case is covered in the initial design specification. I'm also a great fan of concordance generators to identify and eliminate "overloading" variable names within a project. Ever hear of one?

Comment Re:35? (Score 1) 376

I'm 61, and still love solving technical challenges and learning new shit, so I still code...and it helps that I have skills that many consider "antiquated." In the case of my current job, knowing intimately the details of RS-232 based communication and drivers for same -- how to correctly program the NS16550 and ASIC cell equivalents, and more importantly how younger coders MISprogram the chip -- puts me head and shoulders over some of the new grads. Having more than 40 years' experience in project life cycles also means I can set priorities that make sense. I'm willing to adopt any new buzzword that makes sense...but reject new principles where I can't see any advantage to the company and myself.

I've seen the results of a tendency for people to be distracted by "shiny", and work through the problems it causes. For example, I remember when my company embraced virtual machines without fully understanding our system and network environment...and we are talking long-time certified networkers who don't fully grasp how TCP buffer-fill management works and how it affects dataflows, even when quoted chapter and verse from R Steven's book TCP/IP Illustrated. ("He doesn't know what he's talking about.") I fixed the problem, and no one liked my solution. The fact it worked was lost on them. Se la vie.

I don't play nice with stupid or shallow people, so I don't have to worry about management. I was a manager for a while, and my employees said I was the best manager they had seen. What tripped me up is that I couldn't lie to customers, even when told to. That inability to lie convincingly cost me a nice job and pension, but it also cost the company a seven-figure breech-of-contract lawsuit judgement. So I will stay where I am, doing cool stuff, until the day I'm forced into retirement.,/p>

Comment Re:Can Iowa handle a circus that large? (Score 2) 433

Unfortunately, the tendency of The Powers That Be to use heavy-handed government intrusion against those who would speak against their positions is a real problem. I'm not posting this anonymously because I don't expect retaliation to these thoughts; if I did think that someone "official" would take note, I would click that box. And before anyone gets their partisan hackles up, the abuse of government power is not the actions of one political party. Or the actions at one particular level of government -- intimidation occurs in some States as well as at the Federal level.

Comment Re:Because NOT (Score 1) 165

The NTSB says they recovered the engine and NOX tank. No evidence of explosion in those components. Now, perhaps you are thinking of a different kind of explosion, such as how BOAC flight 781, a de Havilland DH.106 Comet 1 exploded -- a fuselage failure instead of engine failure. According to forensics after the wreakage was lifted from its watery grave, inspectors concluded that the aircraft had broken up in mid-air. If SpaceShipTwo experienced a similar type of failure, it could explain how one pilot survived -- he could have been blown out of the aircraft like that captain flying British Airways Flight 5390, who found himself "out in the breeze" after a windscreen failure, and who survived only because he didn't get pulled completely free and fell.

Or perhaps you were talking about the 2007 ground test of the rubber-fueled engine, where the three engineers were standing inside the danger zone when the test went wrong. That's why you run tests, to find out if things do go wrong, and you take proper safety precautions. To compare that failure with this one just doesn't hold up -- they are two different failure modes.

Comment Why EBCDIC? (Score 1) 928

Actually, EBCDIC was weird because it's tied so closely to 80-column Hollerith encoding. Back in those early days of BCDIC encoding (which pre-dated EBCDIC), conversion of card hole punches was done with actual wires, plus a few transistors (or tubes!). When the System/360 came along, the engineers used the same techniques to decode card column patterns "at speed". I learned this for myself when I had to write a driver for a minicomputer (GA SPC-16) to interpret the punches. I didn't have enough words to use a proper 4096-entry table, so I had to use the same tricks to do a 1-of-n selection of the digits field, and then use the three bits from that and combine with the five bits of zone field, and look up the correct value in a 256-character table. The generation of the punch solenoid pattern used the same table in reverse, saving space at the expense of CPU cycles. In a 16-bit machine with 32 users, space -- especially low memory space -- was at a premium.

http://en.wikipedia.org/wiki/EBCDIC

One advantage of doing the punch portion of the driver that way was that there was no way for anyone to cause the punch to generate "lace cards", like the earlier, clunkier driver did. Great way to destroy the card punch we were using, as the power supply in the external box was too small to drive ALL solenoids for ALL columns of a card, especially card after card. The Field Service people told stories of the damage they found at customer sites because of lace-card punching. The FS people were relieved when the new driver proved to prevent the problems.

As I recall, there was an "ASCII mode" in the decimal arithmetic instructions in the S/360 and follow-on systems so "zero and add packed" (ZAP) worked just fine in dealing with ASCII source data. The conversion of the sign was a bit of a problem, but most ASCII input didn't try to encode the number sign in the last character anyway.

Did you know that one of the early porting targets for Unix was a System/360 computer?

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