GPRS and http

[Duncan Mole]

Hi I posted on this last week so apologies for bringing it up again but so
far after having been put on the right track (Thanks Alex F) I have found no
further resources and am a bit dumbfounded.

Can someone explain in (very!) simple language the steps I need to take to
connect to a web server using an external GPRS modem in order that I may use
HttpWebRequest. Also what each step does for me for example AT commands
to....., RAS for..... Connection Manager for....

I have no problem with p/invoking and I am not really in a position to be
buying licenses so you can give it to me straight. ;-)

 

[Adam Goetz]

Completely off the top of my head:

Have a GPRS enabled Sim card in the unit.
Create a GPRS connection through the built in Connection manager - how hard
or easy this is depends on what version of CE/PocketPC you are working with.
Manually connect and surf some pages (assumes GPRS connection isn't limited
to single destination VPN server) to check that the GPRS connection is
working.
Try calling your HttpWebRequest code through this manual connection. Of
course assumes that your target address is accessible via the GPRS
connection you have - an internal at work IP won't be without port
redirection on you primary gateway for example.
To programmcally connect to GPRS you can:
Tell the system to give you a network connection and see if it figures out
to start GPRS by itself (this depends mainly on just how many networks your
unit is capable of and what the defaults are) - draw back is that you cannot
stop the connection from within the program.
OR
P/Invoke a couple of RAS... calls which will let you specifically start and
stop your GPRS connection.

No need for AT commands for the connection itself - however things like
signal strength can be obtained via AT commands, this really depends on your
app as to whether or not these are required however.

Hope that this helps and expect someone to come along and tell you things
I've left out or alternate paths that they recommend.

 

[Duncan Mole]

Completely off the top of my head:

Have a GPRS enabled Sim card in the unit.
Create a GPRS connection through the built in Connection manager - how
hard or easy this is depends on what version of CE/PocketPC you are
working with.
Manually connect and surf some pages (assumes GPRS connection isn't
limited to single destination VPN server) to check that the GPRS
connection is working.
Try calling your HttpWebRequest code through this manual connection. Of
course assumes that your target address is accessible via the GPRS
connection you have - an internal at work IP won't be without port
redirection on you primary gateway for example.
To programmcally connect to GPRS you can:
Tell the system to give you a network connection and see if it figures out
to start GPRS by itself (this depends mainly on just how many networks
your unit is capable of and what the defaults are) - draw back is that you
cannot stop the connection from within the program.
OR
P/Invoke a couple of RAS... calls which will let you specifically start
and stop your GPRS connection.

No need for AT commands for the connection itself - however things like
signal strength can be obtained via AT commands, this really depends on
your app as to whether or not these are required however.

Hope that this helps and expect someone to come along and tell you things
I've left out or alternate paths that they recommend.

 

[Duncan Mole]

Hi Adam,



Thanks for the info. I'm gonna try the manual connection when I can get my
hands on a company SIM tomorrow.



I think I am slowly getting there now. I believe OpenNETCF have wrapped
Connection Manager so I can use that to create a connection from code. I
then use RAS to kick it into life, do you know which calls I will need? As I
say I think some of this was answered last week but that thread seems to
have been mysteriously removed from the board.