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The History of Ethernet
Z34107 tips an article at Ars about the history of ethernet, from its humble beginnings at Xerox PARC in the mid-'70s, to its standardization and broad adoption, to the never-ending quest for higher throughput. Quoting:
"It's hard to believe now, but in the early 1980s, 10Mbps Ethernet was very fast. Think about it: is there any other 30-year-old technology still present in current computers? 300 baud modems? 500 ns memory? Daisy wheel printers? But even today, 10Mbps is not an entirely unusable speed, and it's still part of the 10/100/1000Mbps Ethernet interfaces in our computers. Still, by the early 1990s, Ethernet didn't feel as fast as it did a decade earlier. Consider the VAX-11/780, a machine released in 1977 by Digital Equipment Corporation. The 780 comes with some 2MB RAM and runs at 5MHz. Its speed is almost exactly one MIPS and it executes 1757 dhrystones per second. (Dhrystone is a CPU benchmark developed in 1984; the name is a play on the even older Whetstone benchmark.) A current Intel i7 machine may run at 3GHz and have 3GB RAM, executing nearly 17 million dhrystones per second. If network speeds had increased as fast as processor speeds, the i7 would today at least have a 10Gbps network interface, and perhaps a 100Gbps one."
...does not feel much faster than my MacPlus, because operating system and software makers managed to slow everything down again using "advanced software engineering techniques."
10Mbps was huge at the time. It was much faster (proportional to need) than any of the other components in a computer system. So it's not really surprising that it hasn't quite kept pace. Many home networks are still 10Mbps, and that's plenty for two or three computers.
Q: is there any other 30-year-old technology still present in current computers?
What about SCSI? or RS-232? not as omnipresent as Ethernet but still more or less common. Happy birthday Ethernet, but you are not the only remaining dinosaur...
Keyboards? The plug on the end changed...the keys stayed the same.
--Welcome to the Realm of the Hawke--
Yea, I agree totally, we don't need fast processing or networking.... except for those times where we do. That's why I bought a car with a top speed of 30 miles per hour. I mean, I don't need a car that can go faster, except for when I'm driving on a road with a higher speed limit. In fact, I buy everything with a maximum capacity of my average use, rather than my peak use. That's why my house has zero bedrooms and zero bathrooms. I worked out the math, and I don't use either one of those stupid things anywhere near 50% of the time.
It's hard to believe, but how many of you fuckers were even born yet in the early 1980s?!
10Mbps is not an entirely unusable speed? That's .... Fast Ethernet!
you are a refreshing troll, keep up the good work !
Jehovah be praised, Oracle was not selected
if the situation needs, I got pissed off at our IT dude trying to bounce a wifi signal over 5 repeaters though real 3 hour fire walls and steel beams, I swiped a box of cat3 out of the storage closet and even though its 10mbs, that's 10x faster than our internet and I don't have to hear "my email doesn't work" 50 fucking times a day
.... was the loading of a still image.
Life takes interesting turns, but the most interest is when you're off the beaten path.
If you have a bad cable/connector, 10MB/s can be much more reliable than 100MB/s.
In the 1980s, ethernet tended to be over Thinnet or Thicknet. I seem to recall speeds of 1-3Mbps over those technologies. Twisted pair came out somewhere around 1990 at 10Mbps.
Today I mostly use 1Gps, but deal with servers that are 10G.40G and 100G will be standard in datacenters in a few years.
The blurb indicates that Ethernet is the only technology that we are using from 30 years ago. Back then all the machines I used had Memory, cpus, displays, and keyboards. The particualr technology changed - just like Ethernet technology's changes.
Where law ends, tyranny begins -- William Pitt
10Mbit is still faster than my internet connection. I wouldn't complain, but it seems every streaming site assumes I have at least 5 Mbit and I only have about 1.5. It's amusing to me, because we still have problems with broadband penetration in many parts of the USA and 1.5Mbit is equivalent to the standard T1 speed that many small to medium businesses still use for their WANs.
Gamingmuseum.com: Give your 3D accelerator a rest.
H. L Mencken you figured out back in 1924.
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
i know there are applications that need it but when it came time to look at 10gbps where i work only backups seemed to benefit from it. then we would need to buy all new servers as well.
1. Backbones. If you have a big gigabit switch connected to another big gigabit switch you don't want a single gigabit connection between them. Similarly, when computers come with 10Gbps ethernet you won't want a single 10Gpbs connection between the switches.
2. As more computers come with SSDs, the LAN becomes the bottleneck when transferring files, not the disk. 10Gbps should be enough for them for some time though.
I opened my mind, weighed up all the evidence I could find, and concluded you're full of shit.
True. And if 10 MBit/full-duplex isn't working for you, you can always chop that down to 10 MBit/half-duplex if needbe.
How is the server going to force the client to change its address?
Most major (and properly configured) networks tend to ignore traffic from the wrong IP address on the wrong physical port (so if the DHCP server tells you that your lease expired and your new address is xxx.xxx.xxx.xxx then you just won't be able to use your old address anyway).
Greylisting is to SMTP as NAT is to IPv4
Supply and demand addresses this. We simply do not need a great deal of network speed at this time. For years network bandwidth stagnated simply because no one had a burning need to do more with it. Then our workstations became capable of processing more data faster, thus we moved from 100mbit to 1gig over a very short period of time.
I'd be willing to bet that there is a correlation between HD sizes and network bandwidth, now that I think about it.
Mod me down with all of your hatred and your journey towards the dark side will be complete!
Serial port - slightly improved over 1980 serial ports, but still compatible
Parallel port - slightly improved over early-1980s parallel port, but still compatible
Keyboard - DIN8 instead of DIN5 and different layout and "softer," but otherwise similar to 1980. Still compatible with a cheap adapter.
Video output connector - VGA, circa 1987, but improved in many ways. Still compatible.
DVD burner - the "cd read" functionality came to computers in the late 1980s, to music several years earlier. Can still read early-80s-standard music CDs.
Oh, and it gets even better:
Hard drive - descended from hard drives in the 1960s. SATA protocols descended from SCSI protocols dating from '80s or earlier.
Power supply - many components are technically equivalent to pre-1980s tech.
Screws, fans, and other case hardware - basic tech predates moon landing.
Standard-shape AC power cable dates back farther than I can remember.
Some other computers of this vintage have built-in floppy and PATA ports. PATA descended from the old IDE standard of the late 1980s or very early 1990s. I don't know if it maintained compatibility or not. On some recent computers you can still run a vintage-early-80s 5 1/4" floppy drive through the motherboard's floppy adapter.
I could go on but I'll stop here.
Hey, if it works, it's efficient, and it's cheap, there may not be any reason to improve it. I don't know about you, but one of my favorite data-recording devices is a pencil and notepad, both of which predate the moon landing by far.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
That 10Mbps Ethernet was hella fast at the time.
Remember, everything was text. No fancy graphics or sounds (except for the single beep tone) ... so a terminal wired right into the mainframe at 9600 baud on a serial line was an absolutely screaming connection. Most people couldn't read at the scroll rate of 9600 baud anyway.
Hell, in 1988 when I started university, we still used line editors ... oddly enough, I think it actually was on a VAX 11/780. With a line editor, a 300 baud modem was a usable speed. My connection from home on dialup was every bit as good as the VT52's in the lab, which was good.
Back then, a 360K floppy held a lot of data, and nobody could figure out what you'd do with the 650MB of a CD. Docs were smaller, and the total amount of data we owned was a tiny fraction of what is now one or two MP3s.
I routinely chuckle at the fact that I've personally paid $700 for 16MB of RAM and $350 for a 325MB hard drive ... now I've got 8GB of RAM and a total of 6TB of disk space in my home computer. My first computer had 16K of RAM, and a CPU speed measured in kHz (single digit).
I think the fact that Ethernet is still around is a testament to the fact that it was a well designed protocol from the beginning, and it has been able to scale.
I can only wait to see what kind of wacky stuff we'll be running in just a few years ... and I'm pretty sure there will still be an 802.x transport layer. :-P
Lost at C:>. Found at C.
Heck, the (quite definitely still extant) 1/4inch TRS jack was developed in 1878 for telephone exchange patch panels...
The fan in your desktop PC hasn't changed much since then. (It's a lot different from your laptop fan, or the fans in a VAX 11/780.) And the VAX didn't "come with 2MB" of RAM or have a speed of about 1 MIPS. The canonical definition of 1 MIPS was "as fast as a VAX 11/780", and you could get different amounts of RAM; mine had 4MB in two cabinets. Princeton University's Massive Memory Machine Project later had a VAX 11/785 with 128 MB of RAM, so they could experiment with what you could do if you had "enough" memory (128MB wasn't really quite enough, but it was all you could fit in a VAX expanded to 10 cabinets. :-)
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
If network speeds had increased as fast as processor speeds, the i7 would today at least have a 10Gbps network interface, and perhaps a 100Gbps one.
This sounds similar the the "If cars improved like computers" joke.
Time to offend someone
There's really not much wrong with DHCP. Mature networks offer contracts with durations to clients and then honor them. This is to prevent the client from having to do expensive processing to deal with having the rug pulled out from under it, as well as a recognition that good networks don't just fall away on a whim. A lot needs to happen when an IP address changes, not the least of which is severing and rebuilding any active connections, which must invoke every application owning a connection. If you need to move clients around frequently, you're probably doing something wrong, but you can always reduce your lease time.
Someone had to do it.
If network speeds had increased as fast as processor speeds, the i7 would today at least have a 10Gbps network interface, and perhaps a 100Gbps one."
If ISPs were not trying to screw their customers out of every penny 10G networks WOULD be common place.
Having to work for a living is the root of all evil.
Of course, 9600 baud was really fast back then, and some of them today use 115200 instead. You could crank a Unibus up to 9600 or maybe even 19200 if you had the I/O processor card (KMC?).
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
Floppy is more common on boards than PATA nowadays in my anecdotal experience.
Good-bye
Thicknet with vampire taps ( http://en.wikipedia.org/wiki/Vampire_tap ) to then connect to the servers via AUI connectors.
I'm with you. I think the guy's a genius. Better than the Recipie Troll, Helen Keller and the SCO licensing guy all rolled into one. Dr. Bob is funny, on-topic (in his hilariously off-topic way) and damn smart. Plus, he's somehow got a gift for frist-psotting, as well. I hope he keeps visiting us for a long time to come.
Mods, Dr. Bob deserves an "informative"!
The VAX-11/780 was priced at something like $200,000.
If you buy a comparable computer today, getting 10Gbps interconnects would certainly be a reasonable option.
I didn't know the i7 cpu even had an ethernet interface; I thought it was the motherboard or the add-on card that gave me my network connection. huh, learn something new everyday
-SaNo
If we are going to mathematical about it. What we really need to do is find the average of our use and calculate the amount of variance our usage has, then convert that into a standard deviation and get something that can handle 2 Standard Deviations faster then the average... That that should be good.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
I think SCSI beats IDE on this count. Not only has it been around longer, but IDE eventually had to adopt most of SCSI's features in a painful process of gradually admitting it was the inferior standard. Sorta like USB vs Firewire. And MPLS vs ATM. Etc. ad nauseum.
Someone had to do it.
I used to play a game called "Harpoon 2" (a naval warfare sim) on the original Pentium. Once more than a few contacts were present, it was dog slow. Slow to the point where you'd make some moves, enter, then go get a cup of coffee while the machine thought for a few minutes. Game time would advance by 30 seconds. Repeat. Later I loaded it up on a P4, and was pleasantly surprised to find the game was actually playable.
And that experience was not unique to that one application - just about any application that felt slow on older machines was pretty snappy by the time P4's rolled out. Intel, AMD, et al, simply threw speed at the problem faster than developers could soak it up. I'm hard pressed to think of ANYTHING I use on a routine basis that really bogs the machine down, and that certainly didn't used to be the case. Sure, those folks who do stuff like 3d rendering and similar very computationally intense tasks are still feeling the need for more speed, but really: you wouldn't have even been able to do that stuff on older machines. That's not a case of code bloat.
Over the years I have had the misfortune of listening to Bob Metcalfe shameless claim to be the inventor of Ethernet, and held my tongue out of some combination of embarrassment for Bob, and timidity on my part. Years before that first misfortune, I had the great fortune to speak with David Boggs for some time. He patiently explained the theory behind this new technology, why it was better than others, token-bus, for example, and so forth. So, when this article says "invented by Bob Metcalfe and others" it fails to include the guy whose name appears on the patent with Bob, and is listed first, I believe. I am delighted to see Ethernet evolve so well, and there is room for a lot of fun discussion about how it morphed into what it is, but when we think of this, we should try to honor all the major contributors, especially when they are the technical genius behind the idea. Shame on you Bob. What would your Mother say?
"Bloat" implies useless or unnecessary growth in file size, which is just not what we're talking about here. Sure, simple text files were nice and small, but they were... simple text files. What's your solution? That people stop exchanging pictures, video, and rich text? The tl;dr version of your post: you kids get off my lawn.
You are a quack and I feel sorry for anyone who ever takes seriously any words you say.
Don't know something? Look it up. Still don't know? Then ask.
I'd be very interested to see where you can get a current (by which I mean less than about a year old) computer with RS-232 or SCSI interfaces. SCSI was never all that widespread, at least in the PC (vs. Mac) world - I used to own a lot of SCSI gear, and always had to buy interface card. And I haven't seen a new computer with a serial port in many, many years.
Over the years I have had the misfortune of listening to Bob Metcalfe shameless claim to be the inventor of Ethernet, and held my tongue out of some combination of embarrassment for Bob, and timidity on my part. Years before that first misfortune, I had the great fortune to speak with David Boggs for some time. He patiently explained the theory behind this new technology, why it was better than others, token-bus, for example, and so forth. So, when this article says "invented by Bob Metcalfe and others" it fails to include the guy whose name appears on the patent with Bob, and is listed first, I believe. I am delighted to see Ethernet evolve so well, and there is room for a lot of fun discussion about how it morphed into what it is, but when we think of this, we should try to honor all the major contributors, especially when they are the technical genius behind the idea. Shame on you Bob. What would your Mother say?
when I could look this and other things up without loading a ton of ads and other crap why would i go to ars to read it?
see all the info on ethernet i could want on a single page.. why would i want to go to ars and read it?
I was recently helping my parents pick out a new hub at bestbuy since they needed one solely to add an ethernet port to their network for their tivo to plug into. Speed didn't really matter since it was just for getting subscription data. When we went and found the wired networking stuff they had exactly 2 to choose from. An $80 gigabit switch and a $30 10Base-T switch. Not a 10/100 hub or switch, just a 10Base-T one. I had no idea they still made these lol.
MIDI.
Absolutely agree. Dr Bob is the best troll I've seen on Slashdot for ages. Just when I thought proper trolling was a dying art, he comes along. His posts are well written and self-consistent, and you can almost believe that he's sincere. He consistently gets a large number of replies, indicating that a lot of people are still fooled, every time. Exactly how a troll should be.
I am TheRaven on Soylent News
>is there any other 30-year-old technology still present in current computers?
Yup it is called SCSI. Now in both parallel (going away) and its serial form (SAS).
and FCP (SCSI on fibre channel) is still the main enterprise storage environment, although gradually being replaced by iSCSI (SCSI on ethernet).
Intron: the portion of DNA which expresses nothing useful.
When you give false hope to HIV sufferers then you are very likely to lead someone down a false path of recovery that could easily lead to that persons death.
You are worse than a troll. You are dangerous.
Don't know something? Look it up. Still don't know? Then ask.
here is..."ludicrous speed".
Now this really dates me. But in 1975, I got a tour of Xerox PARC when I was taking a summer course in computer architecture at UC Santa Cruz. Alan Kay showed us some of the early Alto machines. They were still having trouble getting a smooth phosphor coating on the custom-made page-sized CRTs. We saw the PARC 3mb/s Ethernet, which Kay described as "an Alohanet with a captive ether," the first networked file server, and the first networked laser printer. It was clear this was the future, if the price could come down by about a factor of 10. Kay was hoping that some day a workstation might cost as little as a grand piano.
At Ford Aerospace, I was responsible for putting in the first Ethernet, around 1981. It was mostly "thick Ethernet" at 10mb/s. Ethernet cables weren't standard items, but Ford Aerospace routinely built cables for satellite ground stations, so we had the appropriate cables made up and pulled through the telephone ducts run through the building's concrete floors. I checked out a time-domain reflectometer from the measurement equipment pool and took a look at the cable. Cables ended in PL-239 coax connectors, and sections were joined with a barrel. The Ethernet tranceivers had SO-239 connectors on both ends, so the cable went through them. We used a vampire tap once or twice, but it didn't work out as well. The TDR showed a transceiver as generating almost no reflections. But bending the cable tighter than a 1' radius caused a noticeable impedance mismatch.
We were bothered that coax Ethernet wasn't a balanced system. There's a DC component to the signal, which means you can't use decoupling capacitors between sections to get rid of hum. We spent time on grounding issues and looked at the cable signal with scopes a lot. Repeaters were very expensive then, and we were trying to avoid them.
The network interfaces were mostly 3Com boards. Our original network consisted of a PDP 11/70, a PDP 11/45, a VAX 11/780, and a PDP 11/34 used as a gateway to a 9600 baud leased line "backbone link" to Ford HQ in Dearborn MI. We later added four Sun 2 workstations and a Sun server. Everything ran TCP/IP. Ford HQ had a similar link to Ford Aerospace in Colorado Springs,which had an ARPANET IMP. So we could get to the ARPANET over a 9600 baud shared backbone. We could FTP files instead of mailing tapes! I used to Telnet into Stanford's machines over that link.
I did a lot of work on 3COM's TCP/IP implementation, which originally was totally incapable of coping with a mix of speeds in the network. That's why I have those RFCs on network congestion with my name on them. This was before telephone de-regulation, and that 9600 baud leased line was expensive.
The article mentions that "There used to be a lot of fear, uncertainty, and doubt surrounding the performance impact of collisions." There was a period around 1984-1990 when coax Ethernet performance in practice was much worse than theory predicted. The problem was finally figured out by Wes Irish at Xerox PARC. It turns out that the defective design of a SEEQ Ethernet interface chip was causing the problem. As the state machine of the chip transitioned at the end of receiving a packet, there was a period of a few nanoseconds when the chip momentarily turned on the transmitter power, jamming the coax for a few nanoseconds. This reset the "quiet time" timer on all the other stations on the cable, causing them to ignore any following packet for several microseconds, after which they dropped back to the proper "look for sync" state. Back-to-back packets thus lost the second packet, which caused retransmissions and killed performance, but didn't show up as a "collision" to the controll
The Xerox Parc standard was 3 MBps (actually something like 2.96 MBps). The actual throughput was lower because the cards didn't include DMA, and yet this technology sufficed through the early 1980s.
The question of whether network has kept pace with computing is a good one. I would think that the throughput requirements are dependent on the application and not the speed of the computer. Current networking seems to deal fine with high resolution video streaming and application transfer in spite of the speed of the host computer. Yes I have 4 3Ghz cores on my laptop, but most of that is power consumed by compiling and virtual machines. My TV set with its 1 Ghz MHz ARM processor does well with the 150 MBps wireless connection for video and data.
All this talk about the original ethernet spec.. Who remembers (and worked with) ArcNet? The company I worked for in 1987 did quite a few installs of the then VERY new Novell Netware 2.1. The platforms were Compaq 286 desktops with 2MB of ram, a 300MB ESDI drive, and an ArcNet network interface card, and ran NW in "non-dedicated" mode, meaning someone used the system also as a workstation. The fun part of setting those systems up was running a utility called "Compsurf" on the drive, sort of a disk tester/low level formatter combo. We started compsurf on Fri evening just before going home, and it was just finishing up Mon morning... Also loved (NOT) the address dipswitches on the Arcnet cards that were so easy to get wrong... Ah memories...
THANK YOU, Edward Snowden!! Americans owe you a debt of gratitude (whether they know it or not..)
Copy a 500GB system image to a NAS over 10Mbit and get back to me (should take about 4.7 days).
That's why several recent backup tools do the copying gradually in the background, even if it does take days. Consider that most people's connections to the Internet aren't substantially faster than 10 Mbps, making the connection between the LAN and the Internet the bottleneck in a remote backup. (Those with the 100 Mbps connection are outliers, not part of the mainstream that enjoys economies of scale.)
"By all means let's be open-minded, but not so open-minded that our brains drop out."
- Richard Dawkins
If all else fails, immortality can always be assured by spectacular error.
agreed, Dr. Bob is doing it right.
The only enhancement I can come up with would be to branch out into homepathy. That really gets the nerds in a lather.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
you're out there, man... in the Ether(net). You should try some Hash.
mind you, most of the people on /. can easily research this information and verify/debunk whatever the Dr. is trying to claim.
a 50 year old 3 prong, grounded electrical cord which is interchangeable with all kinds of technology.
And, I traveled in asia with a descendent of the guy who invented the screw in light bulb.
Nobody has mentioned the absurd price of early ethernet implementations. There is good reason why it took forever to catch on. It took a cost plus military budget to afford it.
Well Dr Bob the fact that you think you can cure diseases like kidney problems and cancer by tweaking someone's back? It kinda makes you a bit of a loony.
As for TFA? if it ain't broke why the hell fix it.Ethernet works. It works damned well, it works no matter the OS, it works across hardware manufacturers without needing any funky drivers. Frankly that is more than i can say for sound, graphics, hell even certain southbridges are more fiddly than Ethernet. And I can take this 10 year old former school PC I have sitting in front of me, plug it into a 2 year old router and transfer files from my 1 year old desktop. That's nice.
So personally I say "Go Ethernet!" as year after year you remain the same rock solid standard I can count on, without needing dongles and adapters and all the other bullshit. Now if only we could get whomever is in charge of video outputs to make up their damned mind, between the DVI, HDMI, DisplayPort ARGH!! Just pick one and make it fricking universal already!
ACs don't waste your time replying, your posts are never seen by me.
So you say you don't have dual bonded 10Gb Ethernet on your i7? Pity.
Back then 10Mb/s was the high end, today multiple 10Gb/s are. So we have a factor of >1000 here too.
thegodmovie.com - watch it
Heck, some such movies even had a twist ending. The late Richard Jeni once joked about loading pornography on dial-up: "All right, all right, good boobs, all right, come on- PENIS! Oh, God!"
I have an old Pathoclast that I'm restoring. I'm just not sure how to tell if it's actually working.
It will be donated to the James Randi Educational Foundation's new LA headquarters when the move is complete.
-- I have a private email server in my basement.
You may not buy cars with a top speed of 30 miles per hour but you do have to obey speed limits. Where I live the top speed that someone can drive at is 120km/h. Meanwhile, my car can drive faster than that, but it won't and there isn't any foreseeable circumstance where it would. This means that if you buy a car specifically because it can go over 180km/h but the fastest you will ever drive it in the car's life cycle is 120km/h then... you are an idiot who blew all your money on a feature that you will never take advantage from.
This also applies to today's processors. If you need a computer and you end up doing only mundane things such as run office applications, browse the web, communicate and watch videos then if you spend tons of money on a small super-computer that means that you are an idiot who blew all your money on a feature that you will never take any advantage from. Instead, you can spend a fraction of your budget on a system which is anaemic by comparison and you will never know the difference, and keep a huge wad of cash (which you had to work for) to spend on something else. Or even, god forbid, take some free time from work to do anything you'd like.
Slashdot, fix your code or at least hire someone who is competent at it to do it for you.
I'll bet the author of this article was born after 1980 and didn't experience these things first hand like many of us did. This is another article in a series where kids discover older technology and wonder how we got anything done.
Let's have an article about the room at General Motors in the 50s where the 100+ clerks handled accounts payable invoices. The guy I talked to was responsible for vendors starting with JA through JG. Do we really care?
If I used a sig over again, would anyone notice?
You're failing to see that there are times when that max speed is a byproduct of another useful feature. For instance, my car can top 250km/h and I will never get it anywhere near that speed. But I am capable of accelerating to get out of a tight spot when I am traveling 120. It is possible for me to overtake vehicles on a 2 lane road where my wife's 4 cylinder crossover could not. I am capable of pulling out into traffic and accelerating to flow of traffic on busy roads where my wife's vehicle couldn't. This is all because my car has the torque and gearing that comes with a >250km/h vehicle.
There are many times when mundane tasks such as running office application, browsing the web and watching videos run up against anemic system barriers. A netbook from 3 years ago should be able to do all of these things proficiently, but try copying a large amount of data from one Office program to another while having a few other programs running and you'll quickly hit your page file. How about watching a video while this is happening? Yes, all of these things still work on the anemic system, but sometimes it's worth the extra money to not be bogged down during the outliers.
DHCP is, unfortunately, still in full glaring view. An address assignment protocol that doesn't let the server force a new address? Who does that?!
Well, you can use nice features commonly available todays switches together with DHCP:
- dhcp-snooping -> prevent dhcp replies anywhere but trusted ports (if not avail use dhcp option 82)
- arp protect (hp), dynamic arp inspection aka "dai" (cisco) -> allow traffic only from the ip-addresses wich were assigned by dhcp.
You should use simultaneously both. Most manageable proper switches which aren't older than 5 years implement these features.
About the dhcp-lease length you should understand that dhcp-lease is a contract between client and server without option to recall. You need to wait till contract expires and you don't need to permit extension ie. let the client use same addresse again. It's simple as that.
If you think how the hell you are going to change ip addresses in the net controlled manner? Son, you should study the use of secondary addresses* in the interface and let clients have time to change the address when contract ends.
*) edit the router network interface so that you will have simultaneousy the new addresses and old addresses active, this can be achienved by (Cisco IOS -terms) using the secondary addresses, like this:
current: want to change to 172.16.0.0/24
interface vlan 700 ....
ip address 10.10.10.1 255.255.255.0
!
temp:
interface vlan 700 ....
ip address 172.16.0.1 255.255.255.0
ip address 10.10.10.1 255.255.255.0 secondary
!
final stage:
interface vlan 700 ....
ip address 172.16.0.1 255.255.255.0
!
You get the idea from there, it's not the complete interface config.
Then later when you observe (use "sh ip arp") that all the clients have changed addresses to subnet then you remove the secondary ip addresses. Very simple and works well. It's the recommended practise.
And ofcourse if you know, you need to change addresses shorten the dhcp-lease time in good time and you don't have to wait so long before cleaning up the temporary secondary addresses.
Holy moly!
I heard of this stuff in the past but never gave it much thought since. Just googled it and found lots of crap, but this video takes the cake.
Thanks!
Trolling is a art,
You may not buy cars with a top speed of 30 miles per hour but you do have to obey speed limits.
The speed limit is a maximum; what the car with a top speed of 30 needs to worry about is the speed minimum.
Just be glad that someone invented it! Worked at a company that started with a few engineers and a handful of Macintosh IIx machines on AppleTalk. When we grew to a 10-way AppleTalk network, it was pitifully slow. One day, Joe (his real name ;-), came back with a StarNet controller/hub. A bit of twisted pair later, we had a fast network once again! Not sure exactly how close to Ethernet that was, but it was sure faster than AppleTalk! Later migrated to 10Base-T (and were outraged when Apple's Quadra machines arrived and needed a 10Base-T AAUI adapter costing another 100 bucks!). Having to support multiple kinds of transceivers, including coax probably slowed down the adoption of Ethernet technology. Coax had lots of connector issues, something I still see with my Cable TV installation every now and then. These days, I only use 1000Base-T, because packet LATENCY is much lower, and much of the time that's probably more important than overall throughput being higher. Sure, wireless is constantly evolving and almost can't be avoided with modern mobile devices, but fast wired still seems far more reliable.
$2600 in the 80s is probably worth about $10,000 now, or more.
Using the CPI for inflation, it would be approximately $6788 in 2010 dollars if you are calculating from 1980 or it would be $4512 if you start at 1989.
Can you imagine spending even $5k for a computer now? Or $2k?
Umm, yes. Have you looked at the price of a Macbook Pro? It's not remotely difficult to spec out a Windows or Mac computer that costs significantly more than $2000, and $5000 is not that hard to get to either. Fortunately there is often no need to spend that much but it's not hard to imagine.
They were essentially similar to early USB:
http://en.wikipedia.org/wiki/Transputer#Links
"The basic design of the transputer included serial links that allowed it to communicate with up to four other transputers, each at 5, 10 or 20 Mbit/s -- which was very fast for the 1980s. Any number of transputers could be connected together over even longish links (tens of metres) to form a single computing "farm"."
For a time in the 1980s, with five transputers (four borrowed), using a link endpoint to drive a robot, I had the fastest (or maybe second fastest) computer (cluster) on Princeton's University's campus (in a robotics lab I managed). But it was awkward to program it in Occam. And eventually I had to return the borrowed transputers.
What the transputers could have become... Sad they ended up in the dustbin of history...
A 21st century issue: the irony of technologies of abundance in the hands of those still thinking in terms of scarcity.
I prefer an oilstone myself
Yes, I know most don't come with a floppy drive, but if you really want to hook one up, you still can with most systems (not all).
I've had an external floppy drive with a USB connector. Do they make computers without USB ports?
OOOHH!! OOOHH! Yes! Or aroma therapy!!!
However PATA is easy to find on expansion cards while floppy interface cards seem almost nonexistant.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
BTW you have to be careful about forcing full duplex modes because forcing a mode often disables autonegotion. So if you force 10 megabit full duplex on your computer and connect it to an unmanaged switch (or a managed switch in autonegotiation mode) you are very likely to end up with a duplex mismatch (since in the absense of autonegotiation information the unamanged switch will assume half duplex)
Duplex mismatches in ethernet result in a line that sorta works but with appalling performance.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
In your otherwise observant post, you had the line "Gate's Law: Every 18 months the speed of software halves." If this were true, the speed of modern software would be comparable to that of any other point in computer history. In truth, the rate of slowing is slightly in excess of that of hardware driven speed gains. I would suggest the next version of your post should read "Gate's Law: Every 16 months the speed of software halves".
"People don't want to learn linux" hasn't been a valid excuse since '03.