Where's Our Terabit Ethernet?
carusoj writes "Five years ago, we were talking about using Terabit Ethernet in 2008. Those plans have been pushed back a bit, but Ethernet inventor Bob Metcalfe this week is starting to throw around a new date for Terabit Ethernet: 2015. He's also suggesting that this be done in a non-standard way, at least at first, saying it's an opportunity to "break loose from the stranglehold of standards and move into some fun new technologies.""
"He's also suggesting that this be done in a non-standard way"
No, he suggested that five years ago
We don't yet have the technology described (wave division multiplexing) in our homes because very, very few of us want to bother with fiber in our homes at all.
You can push an amazing amount of data over glass, no one would claim otherwise. You can't, however, drape it across the floor and up the stairs to your switch for a quick LAN connection... Not only does terminating a fiber suck, the first time the dog steps on that little yellow wire, end of connection. By contrast, I've used Cat5 as a structural material (tied a PC to a hook on the ceiling with it) WHILE USING IT for data.
So no, we won't see terabit ethernet anytime soon, unless someone figures out a way to push it over copper.
Has this guy done anything relevant in the past couple of decades? Here's a choice quote of his:
Bogtha Bogtha Bogtha
Metcalfe is also known for his harsh criticism of open source software, and Linux in particular, predicting that the latter would be obliterated after Microsoft released Windows 2000: Just because he did something really cool 35 years ago doesn't make him an expert on related matters now.
In a way it can be tweaked a bit, and that has caused a confusion among those that aren't well into the technological difference between Baud (modulation changes per second) and BPS (bits per second).
Anyway - The classical phone modems can have a speed up to 56kbps, but effectively they stay at 28 to 33kbps. And that on a line that actually only provides 3kHz bandwidth. The trick is that in the 3KHz bandwidth you can have a carrier with less than 3000 modulation changes per second, often 2400. In each modulation change you not only have one bit transferred, but multiple bits. This is achieved by having a variation in both phase and amplitude of the signal.
So to utilize the cabling at the extreme speeds that a terabit Ethernet is you may have to resort to the same technique.
There have also been other techniques in use like using multiple carrier frequencies, like what the Telebit Trailblazer modems did. That technology was very resilient to interference compared to the CCITT standards, but it had other disadvantages instead.
If builders built buildings the way programmers wrote programs, then the first woodpecker would destroy civilization.
Not entirely.
There are still a few token rings and other such mesozoic cruft wandering around in the wild out there, but they still work--because some clever folks invented a way to get from one kind of network to another.
Keep in mind, also, that it's really only the early adopters--those who are willing to buy 1st-generation equipment--who would get 'screwed over', and they have, by definition (as the first generation of a given kind of thing is always several times more expensive than the 'production' generations), the money to waste on this sort of thing.
In Xanadu did Kubla Khan
A stately pleasure dome decree
Forget terabit ethernet. I will settle for full, actual 1Mbps (10,100, 1000, etc.) speed for both transmit and receive. Even on my home network, I rarely get full %100 utilization on my LAN. Some PC's are linux, some are Windows. Neither machine ever really reaches its full potential. I looked at other networks as well, even my work LAN, and they have similar issues. I am not a network guru and don't want to spend the time tweaking and configuring. The damn Gbps NIC and network drive I bought should just plug and go and I expect to see speeds reasonably close to 1Gbps, but nope. I see like 1% utilization. Seriously, lets make current technology work as advertised before we start claiming super-fast speeds on other vapor-ware technology. Please?
Jakob Nielsen once famously stated that the "perfect user interface" will require 1Tbps.
Of course I live in America so if I got 2Mbps through my broadband connection I'd be happy.
Besides, it's not like this is going to affect TCP or IP or whatnot--this is way down at the bottom of the OSI model at level 1.
Early research indicates IP protocols will not scale well with high speed links. CPU load goes through the roof and because of limited buffer sizes relative to line speeds, retries and fallbacks plague applications. The end result is a slow, high speed link.
In a nut shell, for high speed links to become useful to a large category of users, IP, and especially TCP must be revamped. Some research has already progressed down this road but late I heard, much more is required.
RAID-5 is EVIL! Never Ever, EVER use RAID-5, You will LOSE DATA! RAID-1 or RAID-10 only for production use.
If you are thinking about Raid-5, forget it, just stripe your drives in a RAID-0 and enjoy the performance benefits and keep frequent good backups and test your restores.
Why RAID 5 stops working in 2009
Why aren't disk reads more reliable?
End of Raid 5
finally, BAARF - Battle Against ANY Raid Five BAARF
HTH, HAND, don't cry.