On Wed, Jan 14, 2009 at 10:03:12PM -0500, Jason Dixon wrote:
> I have a Verizon USB720 dongle that shows up as ucom0. I intend to use
> it for connecting remotely with my X40. I'm having problems when
> packets exceed a certain size. When this happens, the return packets
> never make it back to my system.
>
> I can connect fine with ppp(8). I can ping remote hosts and do
> traceroutes. I can ssh to hosts and perform basic commands. Only when
> the payload exceeds ~900 bytes do things start to fail. This happens
> with almost all TCP traffic, but is most noticeable with SSH or HTTP.
On a suggestion by canacar@, I gave kernel pppd(8) a try. Sure enough,
I'm now getting 2Mbps/300Kbps through the Verizon USB720 (rebadged
Novatel U720) EVDO connection. I can't explain the performance issues
with userland ppp(8) which used to work great with my Treo 700p.
Here is my little script for dialing up. The only other change I made
was 'noauth' in /etc/ppp/options.
####
#!/bin/sh
sudo ifconfig ppp0 destroy 2>/dev/null
sudo ifconfig ppp0 create
sudo route delete default 2>/dev/null
sudo /usr/sbin/pppd /dev/cuaU0 921600 connect \
'/usr/sbin/chat -v "" ATZ OK ATDT#777 CONNECT ""'
sleep 5
sudo route add default `ifconfig ppp0 | grep inet | awk '{print $4}'`
ifconfig ppp0
####
--
Jason Dixon
DixonGroup Consulting
http://www.dixongroup.net/
