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Degrade Your Own Network
cryptonix writes: "This device seems pretty cool. it attaches to your network and allows you to degrade network preformance (for testing purposes only of course). runs on windows and supports gigabit ethernet or 10/100 networks. There's more info at emprix's site about the PacketSphere." Alright, that's funny as hell, and frankly a really good idea.
To gain advantages playing some multiplayer FPS of course. Depending on the netcode of the game, be delibrately limiting your bandwidth at certain times, you can seem to warp around the map, avoid taking damage, etc.
Exactly. With option DUMMYNET and IPFW, you can simulate *any* type of network cloud you like, introduce gaussian error, random latency, and even throttle connections by port/ip/whatever by the bytes and bit rate. Yes, BITS!
It's as easy as:
ipfw add pipe NNN config bw B delay D queue Q plr P
But enough about the amazing FreeBSD system. What I'm trying to figure out is why this network tool--common to any Blackbox catalog-- is now new? I mean, these have been around for decades or more. It's almost like having a story on a new "toaster device" created by Black and Decker that will use electrical heat to brown slices of bread.
Seriously, these devices have been around for a long time, and there's nothing in the link that shows what's new different or exciting...
Mmmmm.... I think someone at the company I work for has secretly had one of these running for years!
I don't know how to put this, but you're an idiot. Seriously.
Network tools have existed for *decades* that introduce error in networks. What are they used for?
Well, let's say you're developing software that handles _anything_ on a network. Sure would be nice to know how it behaves when packets are dropped, delayed etc. Or let's say you're closer to the wire and want to know how the router chip you're programming behaves under simulated load.
But, if you're just a CONSUMER of technology, and don't actually use it for anything useful beyond your own entertainment, then perhaps you have a point; such a device is not useful and should be left to the professionals .
Unfortunately we cant get AOL in Europe
Perhaps not everywhere, but you can in the UK, France, and Germany at least.
-dair
:)
hawk
I have seen something like this device. It's called NetBUI. I know one corp that has over 200 PCs on NetBUI in a LAN and the broadcast traphic is so heavy that Telnet falls over on ocasion.
--= Isn't it surprising how badly I spell ?
It sounds like this device does exactly what the Dummynet feature in FreeBSD (and others, possibly?) does. I've been throttling back NNTP grabs by Leafnode, big downloads, and so on for a while now, to keep my WAN connection from being flooded.
Of course, it doesn't exactly run on Windows...
--- Chris
That all web designers should be forced to work through 56K modem links (so they understand what they put the rest of us through with their flash animations, etc, etc). This device, properly placed in a phone closet, with the latencies turned up ever so slowly between the relevant designers and the in-house servers should do the trick nicely...
A thousand pounds of wood moving at 300 feet per minute. Don't get in the way.
Just set up a pr0n site on a pair of NT PDC's sharing an IP address. You'll be burning out switches in no time.
Just download Sniffit and "Touch of Death" from HERE
Will autokill any connection you see ;-)2 C3AF4F2snlbxq'|dc
--
echo '[q]sa[ln0=aln80~Psnlbx]16isb15CB32EF3AF9C0E5D727
echo '[q]sa[ln0=aln80~Psnlbx]16isb572CCB9AE9DB03273snlbxq' |dc
Uhm, I hate to have to mention this, but why the hell is this News for Nerds??? These types of bandwidth testers have been around for a while!
Get this product announcement crap off here.
A slip of the foot you may soon recover, but a slip of the tongue you may never get over. -Benjamin Franklin
If you want to degrade performance... Who needs another little box on the LAN? (with incomplete software yet.)
MSBPodcast.com The opinions expressed here are my own. If you don't like 'em... Think up your own stuff.
Just place a machine on your network hosting a porn website, a Napster client with 1000's of songs, and a Hotline server with all of the above, plus VCDs and Warez...
Simple. Your bandwidth is gone.
dennis
== Paul Rickard, Editor of The Microsoft Boycott Campaign ====
Well, not as complete and not as a transparent etherenet level device. We don't do reordering
:-)
or packet multiplication and the linux box functions as a router.
The relevant piece you want to use is the `packet scheduler'. There are a variety of scheduling algorithms in there. You might use a command like...
tc qdisc add dev eth0 root tbf rate 1500Kbit buffer 15Kb/8 limit 100Kb
tc qdisc add dev eth1 root tbf rate 1500Kbit buffer 15Kb/8 limit 100Kb
... to throttle your network to T1 speeds. Note that you have to do both interfaces as the scheduler works on outgoing packets only.
I used to have a custom scheduler module that was a packet loser. It turns out to be a bad idea for tcp analysis. (Consider, most of the overloaded routers we meet are running some sort of fair queueing. They are deliberately causing loss to achieve a rate limitation. When you observe packet loss, it is not the loss that causes the limitation, it is the limitation causing the loss.)
For the industrious, as of linux 2.4 I believe a packet loser is much better to implement as a firewall module. Its on my `someday when I have time' list. I also plan a latency module. Nothing like latency to expose chatty network protocols. (cough sqlnet cough, "it worked fine in the development building, I don't know why your global users are complaining"
Agreed, you are dumb! Read the damn article, the device doesn't degrade network by flooding, instead, it does so by perhaps making you lose every nth packet, causing duplicate packets, adding time delays, etc. Did you even freaking read the article? This is a must have for anyone who is running a real network. Try this in a real network with firewall and IDS deployed, they will not notice, no logs or alarms setting off, real life simulation. Sheesh, some people are dumb, people like you.
------ Curiosity killed the cat. {satisfaction brought it back | it didn't die ignorant | lack of it is killing mankind
This ic already part of FreeBSD - it's called Dummynet and was built just for this purpose -to throttle bandwidth and introduce latency for testing purposes. Here's a good writeup by the guy who wrote it/maintains it.
The main reason I want this (and I think any other webdesig firm with a fast connection should have it) is to be able to simulate a modem between your server and your computer. It's a very different thing calculating that the page you've designed will take 50s to load, versus sitting there and interacting with a long latency, slow throughput site until you scream and decide to that maybe that Flash intro isn't all that important.
I'm definitely recommending that my company buy one--does anyone else have any tips on emulating various slow connections (other than buying various speed modems and using a separate ISP :)?
No comment. ... What's a stack?
------
I'm an assembly guru
yah, that would be reeeeeal popular
In Capitalist America, bank robs you!
For that just download some DDoS tools and do it on your own along with a packet sniffer. Or head over to Packet Ninja and download nemesis and inject yourself with crap until your network begs for mercy all at the cool low price of $0,000,000.00
Disgraced
Want Root?
Nemesis allows for all types of injection meaning you create the packet(s) you want to send. So if you start with sequence 1927364 .. 19*365 then 19*400 it still accomplishes the same thing for one.
Secondly many firewalls would filter most of the garbage that program would send whereas using Nemesis along with Fragrouter would allow you to cimrcumvent both IDS, and Firewall as well
Again its still free so STFU clown
Want Root?
Is your network by anychance connected to the internet ?
Unless you have some absolute need for NetBIOS ( like automatic WINS/DNS updating ) you should disable NetBIOS.
It's not useless at all,it provides a host of useful things for your network, but it is also a huge security risk on internet connected systems.
NetBIOS can degrade a large network tho, if you have a few thousand NT boxes all talking to each other the NetBIOS traffic can get rough.Escpecially when they're all turned on at 8 am and announce themselve sto the network.
Having worked on some big LAN/WAN implementations in the past I can say I'd have liked to have this device. The features allow you to emulate "what'd happen if..." - always nice when you're setting up a few hundred workstations on a WAN and some Induhvidual says that a 1Mb dedicated line is sufficient : )
- A picture should be mandatory, especially after that intro text ("tech editors were already exchanging a flurry of e-mail messages about how cool the device looks")
- Price. Sorry, can't seem to find one. Urgh.
Oh, and I must say I don't understand the tech editors at Network Computing much, since I found the box' appearance rather uninspiring. I would very much like to have one at work, though. Debugging flow-control code on localhost is too easy.main(O){10<putchar(4^--O?77-(15&5128 >>4*O):10)&&main(2+O);}
Wouldn't an AOL subscription be alot cheaper?
Someone you trust is one of us.
Why would I spend money on one of these devices, when my users degrade the network for free?
--
Never mind Spamassassin. When's Spammerassassin coming out?
Looks like they are testing it our on there own network....nm, thats the /. effect in full swing.
but I know someone who tested his data link protocol for a cellular modem by shouting into another phone extension. (The protocol had to survive the drop-outs that occur when switching cells.)
--
and let it broadcast appletalk all day long. Ought to do the job nicely.
So for applications that send large amounts of data, without much cpu overhead and harddrive io overhead, this gizmo is great -- but not for those situations where network load is also accompanied by high cpu load as well as many harddrive accesses. In fact, I'd go so far as to say that this thing is completely useless for almost all but the most bandwidth hungry network applications.
...I *really* could have used one of these; every weekend my ex-roommate would download so much porn everyone else's connection speeds would be cut in half... but of course I hear about it three days after the term is over *SIGH*
the coolest club on
there's a much more efficient way to drain network resources from your server. it's called 'counterstrike.'
-- the opinions stated above aren't those of my employer. in fact, they're probably not even my own. you know what, ju
runs on windows
I believe Microsoft already has a product that does this, it's called Windows 2000....
Shunra has been doing this for a couple of years with "the cloud" and storm. http://www.shunra.com. But either way, it's a must have for testing mission critical distributed or client-server apps.
another really cool idea would be to 'sneak' this sucker into your favorite place of business or government and crank it up. not that i advocate this kind of behavior, mind you... but hey, to all my pals in redmond and DC...
The REAL sam_at_caveman_dot_org is user ID 13833.
Developer: "The network is broken!"
Me: "What's the problem?"
D: "We have this nifty client-server application, and it works fine here in Boston, but the clients in London are really, really slow. The network isn't fast enough."
[I examine network trace. The application retrieves a 1000-row table, 1 row at a time. Which is tolerable over a LAN... but at 100ms Latency to London, well...
Me: "You lose! Sorry, play again."
After a few rounds of that, they let me look at a trace *first*. But having a latency generator (bandwidth throttling is fine, but latency is where it's at) would be real handy to check.
for starters, you can test how your business applications will run in a stressed environment. It may be hard to imagine, but a lot of software (custom code especially) works a bit differently under stressful conditions. Think about applications that have dependencies on data from other applications...how do they react when such data takes a bit longer to arrive? btw, this is only one example out of many ;]
"My mother never saw the irony in calling me a son-of-a-bitch." - Jack Nicholson
This thing is huge. I was thinking of something around the size of a 5 port hub for $50. If it's as big as a computer why not do it in software a la Linux style? Hell, you could probably get away with writing a couple of shell scripts to generate traffic and some deliberately bungled iptables mods. Put that on a Linux Router Project floppy disk and your done. Oh, wait a minute. I wonder selling a big box with little chips inside is more profitable? Hey!
Flamebait?
Sorry, it's the best I could come up with within the 4.2 picoseconds I have available to make a FP...
seeing how things, eg. network filesystems, react to heavy traffic, errors and whatever weirdness real networks might face.
this is the kind of tool (stress tester) more developers and beta testers need to use, in order to find bugs BEFORE it gets loose in the real world where these kinds of things normally happen.
runs on windows
IS Windows...
So attaching a device that runs Windows to a network can decrease the performance of that network? We've known that all along...
This
Actually this would be useful to test how applications that are supposed to be deployed over a WAN will work with high latency as well as low bandwidth(what runs on 10/100 ethernet may not necessarily run over a high latency satellite link) addbo
I'm looking for such a tool because I'd like to be able to assess the speeds of doing certain things over a modem link (such as browsing a web site I've designed, or running a particular X application) usinga LAN, as opposed to the bother of actually using a modem. I've considered hacking rinetd around to do it, but no sense reinventing the wheel...
This has been done before! This is does the same thing as when a site is slashdotted
My personal preference is Smart Bits. Handles ATM, Frame Relay, Ethernet, etc. Communicates over TCP/IP. We use it to measure, degrade, tweak, our networking equipment.
there are no stupid questions, but there are a lot of inquisitive idiots
Hmm so what funny uses can we come up with?
John Susek
It would be brilliant to force all web designers to use one of these set to 28.8 against their web server.
Just Plug It In, And It Wreaks
Maybe someone at your isp is testing this device?
10 mbit hubs are quite cheap nowadays. Just buy one and connect all your $$$-switches to it...
W2k AD syncronization between domains would probably be much faster (consume less bandwidth) if Microsoft used these. Unfortunately this thing came to late.
Pull down the console, and type fakelag 1000
www.Jackassery.com
Fragmentation, packet replay, spoof attacks, firewall/vpn interoperability to name a few.
..could have used this when designing Q3's network protocol.
-- If no truths are spoken then no lies can hide --
...but did you see the section its from?
/. stay healthy wealthy and wise.
From the why-the-hell-not dept.
so why the hell not?
anyway, i wouldnt mind one of these every year just to see
You can already do this in Quake III. You can make a toggle key that changes your packet rate to something like 1. It's really hard to rail somebody that's jumping around like that.
If you feel like using up your HD space, you can also take screenshots at certain strategic times. The server stops receiving your packets until the screenshot is written, which makes you appear to stand still. Then you warp to where the server thinks you should have ended up had you not been "lagged." It's really hard to rail an airborne player that skips his apogee.
I got my Linux laptop at System76.
Is this thing worth the money when you can probably find some software do to the same thing? (or just ping -f ;)
And...if you're already experiencing problems with your network, what's this box going to do? Cause more? It's certainly not going to help you diagnose anything!
era-era-boom shakalaka.
Mixmaster Mike on the network! Raise the Latency!
On a more serious note, what happens if you connect several in sequence? Is it like dueling banjos? What about 4? A barbershop quartet?
Maybe it's just laggy.
<p>Isn't network automatically downgrade when a Windows box is plugged to it? No?</P>
<P>My office has three NT servers spewing useless netbios packats day and night, while the Linux server is so busy to ignore them...</P>
a http proxy server like squid has "delay pools" that will limit bandwidth. So for your testing you could login as modem/slow or something and get a speed of a modem user.
Isn't there a nifty software package for linux called iproute2 that does more or less the same thing?
Only to idiots, are orders laws.
-- Henning von Tresckow
I can work for years by hiding that gizmo somewhere at work, fixing the problem then repeating somewhere else in the building.
Woohoo!
Wow, Slashdot does it again. The Shunra Storm has been around longer and is arguably nicer:
http://www.shunra.com/products/storm.htm
--lithboy
The slashdot effect will teach them what network degradation really means. ;-)
kryps
What is the real purpose of degrading a network??? why would it be useful, even for testing purposes???? What can you test?
If you were a true BOFH, what better way to upgrade your servers than by showing your beancounters the small "deficiencies" of your current network?
Linux *is* user friendly. It's not idiot-friendly or fool-friendly!
Why spend money with traffic generation?
All we have to do is connect all Windows machine directly to the network backbone! It's very effective. Here in the university (UFSCar) is how it works!
Forget about switches, routers, etc... Connect it all using HUBs! Connect 2.000 Windows Computers using HUBs and let the network administrator worry about the dam traffic.
Ah, and don't forget to call netadmin, asking why the network is soooo slow!
Never mind. I'm too angry [every|to]day
-=-=-=-=
I know life isn't fair, but why can't it ever be un-fair in MY favor!?
Adtech Data Link Simulators: http://www.adtech-inc.com/products/sx.asp
"Adtech SX series Data Link Simulators create the same delay and error characteristics caused by long distance terrestrial and satellite data links."
Looks like all of the BOFH's across the world will be running out to buy this baby! :)
useless technology looking for some sucker to buy it and figure out what to do with it. Try figuring out what you are going to sell BEFORE you produce it next time.
- Pharao
If the network was constantly being slow and you had to keep fixing it they'd fire you and get someone else who could fix it better.
And miraculously, once they'd fired you the problem would vanish.
Then there'd be a lawsuit.
Then you'd go to jail.
ghaa.
There are a number of products that do network impairments in the market. Our company, PacketStorm Communications (www.packetstorm.com), sells a network emulator that not only delays, drops and reorders packets but provides traffic conditions and packet modifiers. These allow network designers to do "what if" experiment to determine if their network can support the quality of service they are promising.The major users of our product are telecommunincations equipment manufacturers and service providers. And our product doesn't require Windows. These things aren't cheap -- packet-over-SONET, DS3 and ATM interfaces aren't exactly priced like jelly beans. But for the specialized testing required for voice over IP, streaming video and similar applications they are what you need. People interested in trying out network impairments should check the NISTnet web site at the National Institute of Standards and Technology. NISTnet is a linux kernel module that can do basic network impairments. It's available for download from their web site.