Network Monitoring Appliance Looks Below 1 Microsecond 78
eweekhickins writes "Corvil has unveiled a new tool to help network managers cope with increasing pressure to improve performance. This appliance, from the Dublin-based company (with backing from Cisco), passively monitors traffic across networks in segments below 1 microsecond in length and correlates monitoring data with remote appliances and gives a complete picture of latency, jitter, packet loss and other phenomena that affect network and application performance. Corvil CEO Donal Byrne noted that 'If you can drop a millisecond [of latency] off, you're a hero.'"
Drop a millisecond (Score:1, Interesting)
This is the kind of attitude that breeds the Scotty types (you know who you are). If you can cut 2 ms, then only cut 1 ms now and save the other for when you really need it. And when the company is going to spend thousands for analysis, then suddenly cut the last 1 ms.
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Re:Drop a millisecond (Score:4, Informative)
-molo
Time for token ring? (Score:3, Insightful)
I guess that would depend upon where both points are. One has to be on your network. The other ... ?
Now, with Ethernet, one machine can hog the switch (I'll guess that they aren't using hubs). What use is shaving a millisecond off the app if you're still vulnerable to someone else hogging the network at the moment that you're trying to complete your transaction?
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That's what proper network segmenting is for. The guy that hogs the bandwidth usually has some business need to do so (but not always ;). Anyway, say the CAD guys do large file transfers multiple times a day. Well, you segment them off. That wa
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Actually, that is what QOS is for. Segmenting off everyone that wants to do some transfer makes for a fragmented unsummarized network with stretch VLANS all over god and country. Segmenting in little networks is fine...but a disaster in large ones.
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You're missing where one of the parents commented about cases where speed matters. If you're doing algorithmic trading and you're using software QoS, and your competitor is using physical hardware segmentation, your competitor wins (all other things being equ
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All of which just basically proves how shitty collision-based networking is, especially as network size and speeds increase: You have to throw more and more hardware at it, to preserve performance.
The only thing that switching and VLANs do, is attempt to recti
Uh (Score:2)
When did wired Ethernet become CSMA/CA, and what decade are you in? Collision-based networking? The CD in CSMA/CD has been irrelevant after almost a decade of full-duplex microsegmentation, effectively rendering the MA point-to-point, rather than "multiple access", and throwing out the CS in favour of "empty your buffers as fast as you can".
If you
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When did wired Ethernet become CSMA/CA, and what decade are you in? Collision-based networking? The CD in CSMA/CD has been irrelevant after almost a decade of full-duplex microsegmentation, effectively rendering the MA point-to-point, rather than "multiple access", and throwing out the CS in favour of "empty your buffers as fast as you can".
Even your 'high school senior fresh out of Net+' knows that a broadcast storm will very effectively return your switched, full-duplex, microsegmented VLAN to a CSMA/CD network -- quickly. We have all kinds of fancy tools these days to hack Ethernet to do what we want, such as switches and bridges and routers and spanning tree protocol, and fast routing, etc., but in the end, it's still Ethernet. With a few simple hacks, I can force all of the ports on even the best Cisco switch equipment on a given VLAN
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Broadcast storms can be avoided with even a modicum of proper planning
All it takes is one badly behaving Windows client to create a broadcast storm. :)
That does by no means constitute any fundamental failures of Ethernet.
I'm not saying that Ethernet isn't the best technology available given the options. Its ubiquitousness is part of what makes it the best strategy, though. Realistically, Ethernet is an old technology and a fresh approach, given what we know today, could do much better technically. It has its flaws, and some of them are very fundamental. You're right in that you can hide these flaws through good network engineering and adm
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You can effectively stop broadcast storms at layer 2 with the right implementation, so what I'm saying is akin to saying "Well, sure, you can hack Windows with a few simple scripts, but that doesn't constitute any fundamental failure in the concept of operating systems."
There are of course better things than vanilla Ethernet for regular IP networks, but Ethernet is still a very viable strategy if implemented correctly.
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Most VoIP codecs can work with a maximum of 30ms Jitter. You can't drop below 1ms because of the latency implied by the network equipments (just to go through their hardware takes a few milliseconds - not to mention stateful equipment such as firewalls or load balancers, etc.)
Also, I wonder how they can passively measure latency or jitter - accurately, that is. Network Testin
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Here's a nickel, kid, go buy yourself a real firewall.
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Does this mean that a next step in human evolution is being able to measure time with microsecond accuracy?
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So I guess we've already evolved that far... the next step would have to be inbuilt dart
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Was there any sort of increased packet loss? Also, was it merely an average increase of 0.3ms? If there were any sort of peaks in the latency, i.e. increased jitter, that could be much more noticeable than an average latency increase might suggest.
If your signals travel the speed of light, the propagation delay from pt. A to pt. B (100m in your case) should be around .33us (microseconds). Propaga
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There wasn't any packet loss that I am aware of, some pretty intensive (proprietary) UDP applications operating across the link (there was no TFTP style checks on this) and dropping a packet would have been noticed. Average latency was, (for example) 0.7ms and increased to 1.0ms... some fairly standard diagnostics such as a continuous ping showed no maj
and again in layman's terms?? (Score:1, Interesting)
sorry if I sound stupid. It seems like greak to me. I'm just used wireshark etc
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And that I was "used to" Wireshark.
FYI, my Greek is much worse, than my first language, English. It is even worse than French and Russian, two other languages I can speak to varying proficiency.
However, sir, I am very tired.
At the end of a long day, it is not unusual to think in straight lines while typing nonsense.
Moreover, thank you kindly sire, for asking God to help me;
I needed some guidance to help me past morons like you.
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***
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The breakthrough appears to be that it is the fastest of these type of devices available.
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That just about says it all...
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I managed to miss out more words, and make more spelling mistakes in that single post than I usually do in a week.
I guess I need some more Coffee.
Re:and again in layman's terms?? (Score:5, Informative)
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Please see various other posts of mine, to see why that was uncalled for and unnecessary.
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They timestamp the packet at some point in the network and when it arrives at the other side they timestamp it again to work out the trip time. Not really rocket science, but they seem to have come up with ways of measuring time pretty accurately at two different places and keeping the clocks in sync or working around clock drift in their measurements.
The other part of their system is some algorithmic work that correlates packets and tries to wo
Re:Oh goodie! (Score:5, Informative)
Milliseconds count. Maybe not to your stock tips, but trust me as someone who has spent about a decade in this kind of environment now - sub-millisecond latencies certainly count in automated trading between investment banks/hedge funds/whatever. To the point where people are prepared to pay fortunes to have their machines located physically closer to an exchange.
For fun, check out arbitrage [wikipedia.org], and then ponder again why reducing latency might be important in a competitive environment. Think about highly liquid markets, such as spot foreign exchange.
Cheers,
Ian
buffering ......... (Score:3, Interesting)
A more logical reason would be to reduce the possible traffic issues.
If I'm sitting on the network with a 100Mb/s connection straight to the serve
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Humans make decisions at a minimum of around 200ms I think - that's from memory, so I expect someone to be along and give the real figure soon. But I'm not speaking about humans, I'm speaking about algorithmic trading in a competitive environment. It truly is that significant to remove
Because you can buy faster hardware. (Score:2)
So get liquid nitrogen and overclock your processor.
Speeding up the computer running the algorithm is more productive than trying to get your packet through 1 millisecond faster.
I understand that.
I also understand that if you're LOSING because you're one millisecond
Re:Because you can buy faster hardware. (Score:5, Informative)
Sorry, but do you really think people don't do that level of analysis as well as trying to improve the network speed?
My point is that if you're looking at spending money for a 1 millisecond gain, you've already lost sight of the goal.
The goal in this kind of app is low latency - every millisecond counts. There are other goals of course, throughput, guaranteed maximums as well as low minimums...but in this case we were specifically discussing latency.
And that's not even counting a router or everything that can slow down your Internet connection
Internet connection? Who's talking about an internet connection? Dedicated leased lines direct to the exchange, internal transfer between machines...this kind of stuff isn't One Man And His PC sitting at home trying to day-trade. Yes there's variability, but even so engineering it out as much as possible is certainly an aim.
All the levels of analysis you describe, from the algorithm right through to the NIC, are already being done. At some point they will be done better, because of a change in available tools. This appears to be one of those tools.
Cheers,
Ian
Re:Because you can buy faster hardware. (Score:5, Informative)
Do not assume that the people interested in this level of performance are idiots. There's always the possibility they know more about what they're doing than you do.
doc
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If *everyone* improves their latency equally much, they're all back to square one.
Which is typical of speculation (as opposed to investment) -- its fundamentally stupid playing a zero-sum game when positive-sum games are around.
Still too laggy for FPS games. (Score:1, Informative)
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You'll never go faster than the speed of light (Score:4, Informative)
A beam of light takes roughly 1/7 of a second to travel around the world. That means that if you're playing on a server on the other side of the world, your ping will always be at least 143 ms. That's a hard physical limit: the only way to decrease that time would be to drill a hole through the Earth, or move closer.
Better living through physics... (Score:1, Insightful)
The real latency should be actually much higher due to switching or forwarding overhead and any monitoring that the NSA does. 300ms at least.
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"Much much slower" is a pretty big exaggeration. Propagation velocity using a solid polyethylene dielectric is 66% and that is about as slow as it gets for electrical signals. Some glasses are as low as 50%. Store and forward ethernet switches at 100 Mbits/s have to add at least 150 microseconds pe
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and light in fiber moves slower than light in free space.
Of course UK to USA isn't as much as halfway round the world.
You can get faster than the speed of light.. (Score:1, Funny)
To make your own wormhole:
1. Put your network cables inside garden hoses first as wormholes can be moist environments
2. Take two horizontal clothes washing machines and put them back to back (you can use tumble dryers but its a bit more dangerous - not wet enough)
3. Open the door on each washing machine and take out any socks or coins
4. Drill a hole through each drum and thread the garden hoses through
5. Place a teaspoon of a uranium and a tablespoon of marzip
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Going half way around the world only takes 1/2 of 1/7, or 1/14th.
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It burns! (Score:1)
More seriously though, the article might benefit from a little bit more context. As mentioned above, taking 1ms off network latency is meaningless across long connections, where you expect 40ms latency just from the routers, speed of light, etc. Taking 1ms off when microseconds count, when your latency is 5ms, within a system where automated transactions and big money are involved, then the situation is different.
The readers do not recognize the requirem
RIPE NCC Test Traffic services (Score:4, Informative)
The RIPE NCC [ripe.net]'s Special Projects [ripe.net] group have been offering sub-microsecond latency/jitter/analytical services to ISPs for years. Their data is invaluable and unique, since it measures latency, jitter and packetloss in a single direction (unlike ICMP Ping, which is a round-trip measurement over an asymmetric path) and goes back at least to 2000. The paper claims accuracy to 0.0006 ms, which was good for the time when the product was designed.
Read about the project here [ripe.net] and the paper on TTM [ripe.net] [pdf] that was presented at the PAM2001 conference [ripe.net].
(This isn't what Corvil do.)
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bandwidth provisioning analysis appliance .. (Score:1)
"When it exits on the other side of the WAN, we time-stamp it, and we can correlate the data across the whole network"
Well, doh
'Byrne said Corvil's customer base is "more than 10 but less than 100."'
What ever happened to that perpetual motion outfit