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Using Linux To Make a Slow, Awful WAN Connection
Julie188 writes "This is a brilliant little Linux trick from Windows fanboy Tyson Kopczynski. He wanted to test a new Windows 7 feature called Branch Cache, which caches remote data on the local machine to reduce traffic on a stressed out WAN connection. But how to fake a crappy WAN? Linux. 'The command that I executed (tc) made use of Linux Traffic Control (a kernel thing) which allows me to easily interject 100ms latency on eth1. Boff, Bonk, Pow, Plop, Kapow, swa-a-p, whamm, zzzzzwap, bam ... instant WAN crappiness,' he writes."
Linux has to be forced to degrade network performance. Windows does it automatically.
Did MS ever fix that 10 TCP/IP connection limit?
Linux, 'cause even Windows techs need real tools sometimes.
Why not just use a Vista box and play an MP3?
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how did that windows caching stuff he was testing out perform? or is this article just a synopsis of the man page for a common command .... ?
The problem with slashdot is that most of its users were bullied and stuffed into lockers as kids!
This seems to be valuable in situations where you are developing an application that will be accessing a database behind a dsl firewall. It would be nice to be able to profile the performance on your local network, instead of having it run too slowly to be used in the field. This happened to me once, and I fixed the problem by using a subselect, instead of multiple sql commands, but this wasn't readily obvious as the library was hiding the details of the process, and the speed of the local network compensated for the ineffiency(sp) of the code.
Such capability is very useful to network folks to predict application behavior and best management approaches in various environments. We used FreeBSD for that purpose, but the effect was the same. We injected 350ms latency in each direction, and presto - satellite communication. That is enough to cripple TCP connectivity through a sizable pipe (latency will preclude the flow from taking entire pipe). By testing various acceleration methodologies, you can see first hand which one will allow you to fully utilize the bandwidth you are paying for, all in the comfort of your lab.
End anonymous moderation and posting on
*raises hand*
Intel 8945J integrated wireless on my laptop. Dual boot, Zenwalk Linux and XP MCE 2005. Until the most recent driver from Intel, the wireless card was *significantly* stabler under Linux. It's now just as stable under Windows (though I replaced by router with a new D-Link 802.11n router recently too), but the throughput at long range is still better in Linux.
As an example of the latter under Windows the useable range on my wlan caps out at about 25m. that's enough to cover my house, and much of the front lawn. Under Linux, I was able to connect to my network from the picnic table at the park across the street, about 100m. I was only getting 1mbit of throughput, probably less, but it was definitely getting better error correction and a more useable connection at that range than under Windows.
If you believe everything you read, you'd better not read. - Japanese proverb
Dear lord if you're going to troll... at least get the grammar right:
Linux, 'cause even Windows techs can be real tools sometimes
They were shocked when I introduced them to another tester who tested board games in the 1970's.
Oh wow, so before video games people used to play with pieces of lumber? :D
Fnord.