Re: [Discuss-gnuradio] gmsk in light of fpga modifications

[Brett L. Trotter]

Daniel O'Connor wrote:
> On Thursday 18 January 2007 21:31, Brett Trotter wrote:
>   
>> I realize ssh probably isn't the best thing to test with, but it happens to
>> be a quick and easy way to test file sending. The question is, is our
>> tunnel acknowledging corrupted packets instead of asking for resends? The
>> question I'm asking ultimately is, what would cause corruption of the ssh
>> session?
>>     
>
> I suggest you install something like netcat 
> (ftp://coast.cs.purdue.edu/pub/tools/unix/netutils/netcat/) and see if raw 
> socket connections help things.
>
> Also you might be running out of entropy..
>
>   
Saw the entropy problem when using /dev/random, but /dev/urandom seems
happier- in either case, at some point, ctrl+c's quit working and the
session basically locks up (with scp, it eventually stalls out- the most
I transferred was a MiB)- but typing causes packets to traverse the
tunnel even though the typed text does not render, nor seem to reach the
other end. I ran a ping -A and lost '0%':

117536 packets transmitted, 117011 received, 0% packet loss, time
> 1288562ms
> rtt min/avg/max/mdev = 7.952/10.591/35.604/0.920 ms, pipe 3, ipg/ewma
> 10.963/10.484 ms

So bottom line is, the ssh dies off. I'm going to try out the tcpdump 
suggestion from Greg Troxel and see what things look like.

It's possible that the interface is seeing so many errors that the checksums 
occasionally work out despite the errors- I'm going to also try increasing the 
symbols/sample.