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Hardware

Degrade Your Own Network 88

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.
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Degrade Your Own Network

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  • by Anonymous Coward
    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.
  • by Anonymous Coward
    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...
  • by Anonymous Coward
    Mmmmm.... I think someone at the company I work for has secretly had one of these running for years!
  • by Anonymous Coward on Monday May 07, 2001 @05:22AM (#241048)
    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 [aol.co.uk], France [www.aol.fr], and Germany [www.aol.de] at least.

    -dair
  • It says it runs *on* windows. So I assume it's the apple menu. Err, I mean the highly innovative start button . . .


    :)


    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.
  • by CWCarlson ( 2884 ) on Monday May 07, 2001 @04:35AM (#241052)
    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...

  • 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 [securify.com]

    Will autokill any connection you see ;-)
    --
    echo '[q]sa[ln0=aln80~Psnlbx]16isb15CB32EF3AF9C0E5D7272 C3AF4F2snlbxq'|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.
  • If you want to degrade performance... Who needs another little box on the LAN? (with incomplete software yet.)
  • 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.
  • Just install Outlook on every networked computer. Melissa and 'I Love You' variants will degrade the performance in no time at all... For free!
    This advice provided free-of-charge without warranty.
  • by victim ( 30647 ) on Monday May 07, 2001 @05:31AM (#241060)
    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" :-)
  • by segmond ( 34052 ) on Monday May 07, 2001 @06:33AM (#241061)
    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.

  • 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 [unipi.it] 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 :)?

  • "This device ... attaches to your network ... degrade network preformance ... windows."

    No comment.
    ------
    I'm an assembly guru ... What's a stack?

  • yah, that would be reeeeeal popular


  • For that just download some DDoS tools and do it on your own along with a packet sniffer. Or head over to Packet Ninja [packetninja.net] 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 [disgraced.org]


  • 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
  • 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.
  • by sergente ( 67242 ) on Monday May 07, 2001 @04:44AM (#241069) Homepage
    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 : )
  • Two things forgotten in the review:
    • A picture [empirix.com] 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 [sourceforge.net], though. Debugging flow-control code on localhost is too easy. ;^)
  • Based on the article, it appears that it has a little more flexibility that Dummynet. My understanding is that Dummynet can only do bandwidth throttling, fixed packet delay, and fixed packet loss rate, based on pseudo-random distribution. PacketSphere seems to add the ability to specific an action on every nth packet, can reorder packets in a controlled manner (vs. creating multiple pipes in Dummynet) and Gaussian-based delay rates. These are all things that would be great to see in dummynet. Of course, being that it is open software, I (or anyone else) could, but I hardly have enough time to use the current functionality in dummynet!
  • by selectspec ( 74651 ) on Monday May 07, 2001 @04:38AM (#241072)
    Wouldn't an AOL subscription be alot cheaper?
  • by Yer Mom ( 78107 )
    Why would I spend money on one of these devices, when my users degrade the network <I>for free</I>?
    --
  • by dregoth ( 84089 )
    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.)
    --
  • Don't service packs for NT perform the same function?

  • and let it broadcast appletalk all day long. Ought to do the job nicely.
  • by BierGuzzl ( 92635 ) on Monday May 07, 2001 @04:54AM (#241078)
    The purpose seems to be for testing that VoIP technology, for which nifty little controls on a windows desktop, to adjust latency, throughput, packet loss, etc are really useful. As it turns out, VoIP requires really good network quality to actually function properly.

    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*

  • there's a much more efficient way to drain network resources from your server. it's called 'counterstrike.'
  • Unfortunately we cant get AOL in Europe :( I am waiting for EOL...

    Really? You're lucky. I live in Europe, but I am still swamped with AOL CDs enough to use them as one-time glass mats (nossir, that's NOT the meaning of "one time pad").

    Kiwaiti

  • 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.
  • Personally I didn't think it was that neat looking either. :) But I loved the concept, a PacketCrapper!

    Enough with the "just put windows on your network" jokes. This thing does stuff like bad frames, latency, out of order packets, and so forth across your backbone. Windows doesn't do that (especially when it isn't being a router/gateway/repeater).
  • Just opened the print version (which has a pic :),

    Vendor Information:
    Hammer PacketSphere, starts at $50,000. Available: Now.
  • Come on, you gotta go to the father of network slowdowns, Cliff Stole. Start jingling your keys over the phone punch down to cause short pops and clicks. Thats the best way to keep the cracker online and save our national secrets!
  • 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...
  • 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.
  • There is a similar package called NISTNet. It is an Open Source, runs on Linux. It doesn't have all the features of the Pocket Shpere, but it is free. Bythe way, we are using other software from Empirix and are not very thrilled with quality.
  • by Lizard_King ( 149713 ) on Monday May 07, 2001 @04:45AM (#241090) Journal
    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 ;]

  • This thing is huge [empirix.com]. 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 [linuxrouter.org] 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.
  • by rtscts ( 156396 ) on Monday May 07, 2001 @04:32AM (#241094)
    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...
  • 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
  • Would anyone be so gracious as to recommend a tool that will artificially limit the speed of a TCP connection? It could act like a port bouncer, or even do proxying functions (HTTP proxy or SOCKS) if it was fancy.

    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 ;)

  • Networking companies have been using these for a long time.

    My personal preference is Smart Bits [netcomsystems.com]. Handles ATM, Frame Relay, Ethernet, etc. Communicates over TCP/IP. We use it to measure, degrade, tweak, our networking equipment.

  • Hmm so what funny uses can we come up with?
  • It would be brilliant to force all web designers to use one of these set to 28.8 against their web server.
  • No problem here.

    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.
  • Unfortunately we cant get AOL in Europe :( I am waiting for EOL...
  • Can we simulate a network with Mars? RFC 1149? Cool!
  • by angry old man ( 211217 ) on Monday May 07, 2001 @04:44AM (#241107)
    Bagh,

    Back in my day we didn't AOL or all of this fancy schmancy network performance degraders. If we wanted to slow down network performance, we would just hold the phone handset about 2 inches away from the modem cradle and then loudly shout. Nowadays, all you lazy kids with your fast 100 Mb connections complain when quake 3 doesn't get a ping rate less than 50. If it wasn't for all that wasted bandwidth, the internet would still be only used for DoD research like it was intended, and like any hardworking network should be used for.

    Bagh!

  • Pull down the console, and type fakelag 1000
  • Flamebait? come on... there's a real knee-jerk thing against thoughtful FPs, i say...

    --
  • Fragmentation, packet replay, spoof attacks, firewall/vpn interoperability to name a few.
  • ..could have used this when designing Q3's network protocol.
  • ...but did you see the section its from?

    From the why-the-hell-not dept.

    so why the hell not?
    anyway, i wouldnt mind one of these every year just to see /. stay healthy wealthy and wise.
  • 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.
  • 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 [coinet.com] that does more or less the same thing?
  • by number one duck ( 319827 ) on Monday May 07, 2001 @04:33AM (#241119) Journal
    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
  • by kryps ( 321347 ) on Monday May 07, 2001 @04:52AM (#241121)
    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?
  • by Tricolor Paulista ( 323547 ) on Monday May 07, 2001 @05:25AM (#241123)
    If you were a true BOFH [theregister.co.uk], what better way to upgrade your servers than by showing your beancounters the small "deficiencies" of your current network?
  • 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 [ufscar.br]) 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

  • Adtech Data Link Simulators: http://www.adtech-inc.com/products/sx.asp [adtech-inc.com]

    "Adtech SX series Data Link Simulators create the same delay and error characteristics caused by long distance terrestrial and satellite data links."
  • all you lazy kids with your fast 100 Mb connections complain when quake 3 doesn't get a ping rate less than 50

    What if someone set up a PacketSphere in front of a Quake server? With some clever programming, there could be a latency handicap to equalize the more lopsided games a bit.

  • Looks like all of the BOFH's across the world will be running out to buy this baby! :)
  • Well, if the router is properly configured, it'll drop netbios packets, especially the broadcasts, so it won't matter.
  • 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.
  • 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.

  • 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.
  • I dont agree to this - Shunra can only handle upto 45Mbps while Packetsphere is capable of handling full duplex wirepeed gigabit traffic!!! It also provides 8 full duplex 100 Mbps ports handling wire speed traffic.

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