According to Jorge Matias: While burning my CPU.
> 
>   I have 2 Linux machines configured with TCP->AX.25 at 9600.
>   I'm doing several performance comparison tests between DG and VC. My
> wireless connection is between the two stations has permanently 9+30dB of
> signal strengh.
>   The test is an FTP connection. 
>   Well, with VC I cannot finish any transfer. It does timeout everytime. 
>   With Datagram mode I can transfer files but the best transfer rate I
> achieve is 26bytes/second.
>   What I can see in modems behaviour is that they have long times without
> transmiting.

Then i would say you or your partner are missing packets.

>   I have configured some files in /proc/sys/net/ax25/<interface>/:
> 
>     maximum_packet_length = 64
>     standard_window_size  =  7
>     t1_timeout            = 40
>     t2_timeout            = between 5 and 15
>     (Note: There are only these two stations in the frequency)
> 
>   In command "route" I used irtt=6000ms and window 1728/1792 (216/256 * 8)

I have a 9600 point to point DG-link with a friend, we reach 750Bps, +.

MTU 512
WINDOW 1888

It would seem you need to look at your radio's and modems first, there must
be something wrong.

To test a link i send a series of pings as shown below, dont try my example
on your link, change the -s to suit your MTU otherwise no packets will be
returned.

pipo#  ping -c8 -l7 -s472 -i5 44.137.28.42
PING 44.137.28.42 (44.137.28.42): 472 data bytes
480 bytes from 44.137.28.42: icmp_seq=0 ttl=64 time=4571.4 ms
480 bytes from 44.137.28.42: icmp_seq=1 ttl=64 time=5009.5 ms
480 bytes from 44.137.28.42: icmp_seq=2 ttl=64 time=5447.6 ms
480 bytes from 44.137.28.42: icmp_seq=3 ttl=64 time=5885.8 ms
480 bytes from 44.137.28.42: icmp_seq=4 ttl=64 time=6324.0 ms
480 bytes from 44.137.28.42: icmp_seq=5 ttl=64 time=6762.3 ms
480 bytes from 44.137.28.42: icmp_seq=6 ttl=64 time=7200.6 ms
480 bytes from 44.137.28.42: icmp_seq=7 ttl=64 time=7638.7 ms

--- 44.137.28.42 ping statistics ---
8 packets transmitted, 8 packets received, 0% packet loss
round-trip min/avg/max = 4571.4/6104.9/7638.7 ms

Repeat that several times, then you can get a good idea how the link is.
 
> 
>   Well, I don't know which other information is important to tell?
>   Any comments about this? Why the stations have long times without
> transmiting (max time without tx = 35secs)?
> 
>   Regards,
> Jorge Matias
> 
> - -- --- ------------------------------------------------- --- -- -
>   Computer Science Student at Instituto Superior Tecnico (Lisbon)  
>   A3000/060 32Mb -[Ariadne][MFC III][CV64]- LinuxOS 2.0.36 
>   QRZ: CT2HBZ  - E-Mail: [EMAIL PROTECTED] 
> 


-- 
Regards Richard.
[EMAIL PROTECTED]

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