ndt-users list created

[Peter Van Epp <>]

        The "slowest link is gig" is likely caused by the server NIC card 
having
interrupt reduction (it has a correct name but I don't remember it :-)) on.
NDT guesses link speed by packet interarrival time from the NIC if it delivers
multiple packets per interrupt that timing is disrupted (this can usually be
disabled in the NIC driver although perhaps not easily). Before I turned it
off on our gig link it used to claim I had an OC192 (which was of course news
to me). Throughput looks about right for a well performing 100 meg link 
though. 

Peter Van Epp / Operations and Technical Support 
Simon Fraser University, Burnaby, B.C. Canada

On Wed, Sep 26, 2007 at 01:32:49PM -0400, Jeremy Schafer wrote:
> Is it possible that I have bogus information or is it correct? Here is 
> what the Java applet spit out as information when I did a scan:
> 
> TCP/Web100 Network Diagnostic Tool v5.5.1
> click START to begin
> Connected to 172.28.7.136 -- Using IPv4 address
> Checking for Middleboxes ..... Done
> checking for firewalls ...... Done
> running 10s outbound test (client-to-server [C2S]) .... 93.98Mb/s
> running 10s inbound test (server-to-client [S2C]) ..... 94.09Mb/s
> The slowest link in the end-to-end path is a 1.0 Gbps Gigabit Ethernet 
> subnet.
> 
> Both the throughput numbers and the "slowest link" output are 
> interesting. The NDT client and server are on different networks but 
> they are both connected to their local switch at 100Mb/s full-duplex. 
> Are these numbers still expected? They seem awful high for the speed 
> they should be running at.
> 
> Also, is it possible to change the test from 10s to 30s? If so, do I 
> cause any problems by doing it? I appreciate the help. Thanks.
> 
> -- 
> Jeremy Schafer
> Network Architecture & Applications
> IM: ruoitjeremy
> RUIM: jschafer