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High-Capacity Bandwidth Testing Software?
An anonymous reader asks: "I work for an ISP which specializes in high bandwidth (100+ megabit) fiber-based delivery solutions. As with any other ISP we sometimes have to perform troubleshooting with customers who are reporting slow throughput. We currently have a home-grown bandwidth testing server in order to point-to-point test the throughput across our own network. Unfortunately (fortunately), customers have begun purchasing amounts of bandwidth that are capable of exceeding our testing capacity. Given a multi-gigabit network infrastructure and an on-net server with a gigabit Ethernet port, what software packages are available which can reliably test throughput approaching one gigabit? Cross-browser compatibility and 'click-here-to-test' usability should be considerations."
But I'd start with something like pchar, which will tell you the effective bandwidth at each hop on the network. That will tell you how severe the blockage is and, more importantly, where. It's not the "best" tool out there, but it's reasonably non-intrusive (unlike most stress-testing tools) and I've not seen any obvious problems with it at gig speeds. It does need patching for Linux, though. I sent a patch to the maintainer who has sworn he'll someday get around to including it. NetBSD has a faster network stack, though, and is more suitable for such tests. Which I hate, as I prefer Linux, but facts don't change themselves to suit a like.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
TPTest http://sourceforge.net/projects/tptest/, an open source test suite from "Post och Telestyrelsen" http://www.pts.se/, a division of the Swedish goverment. Even a 200 MHz Pentium MMX running Linux could test a 100MBit/s fiber reliably.
http://dast.nlanr.net/Projects/Iperf/
http://sourceforge.net/projects/Iperf/
Very configurable, and if u want GUI or network tuning.. read the FAQ, they give suggestions.
-- Robi
You should be using a dedicated test set. Using a PC running what ever software isn't going to produce accurate results due to several factors:
1) Process speed
2) I/O reads and writes
3) OS (swapping)
Look towards a dedicate unit (test head) with remote capabilities.
DISCLAIMER: I work in the Telecom Industry.
If you're serious about it, you basically need to give in and spend serious $.
The main game in town is Spirent.
In the IPS & firewall testing world, they're what everyone uses, but even in lots of load balancing applications etc they're what people use.
There are a few software solutions around that do an ok job, but very few that can do much at decent speed (ie > 400Mbit). I have a pretty crack team of devs, and using hand tuned open source, and home-spun apps, we got by for a few years, but should have given in years earlier and just got a set of Spirent gear. You'll save time.
Their Smartbits line are basically hardware based packet generators, able to blast away for a variety of scenarios.
Their Avalanche line are hardware based full session generators, so you can re-create a web server being hammered by thousands of clients. I just signed a cheque for > $100k for a single pair of avalanche boxes however, so bring your cash box...
You'll probably find Spirent's hw based solutions frustrating, but if you work with others doing similar work they're very widely used, and you can exchange scripts etc..
There is an Irish company that was moving in to this space, and had an ok product, but it was a bit immature when I last tried it. Sorry, but their name escapes me- google should know.
--Q
BreakingPoint Systems makes network test hardware that can go way beyond 1 Gbps simulations. You can also capture and recreate traffic at high speeds to better simulate a specific users load.
For testing bandwidth I use Netperf. It's free, extremely customizable in the type of data sent (TCP/UDP streams, packet size, IPv4/IPv6, etc), and quite accurate. The program has no trouble generating enough traffic for a 1Gb link, and it's worked well over 10Gb links too. There's no GUI to it, but setting up a script to start it and report the results is pretty trivial.