To establish a cellular data link, you must configure and initiate a PPP connection. Sample options files and chat scripts are provided in the ppp peers directory /etc/ppp/peers. Anything specific to the network or connection should be placed in one of these files. Global options should be
placed in /etc/ppp/options.

To set up a GSM (G2, H4, H5,radios) cellular data connection using default options:

# Set "APN" to the APN for your cellular provider
# ocg-set-apn added in CoreCDP 2.3.3
# If running CoreCDP 2.2.x or earlier, 
# you must edit /etc/ppp/peers/gsm_chat to set your APN
ocg-set-apn APN

# Dial the connection (using /etc/ppp/peers/gsm config)
pppd call gsm

# Verify ppp0 is up
ifconfig ppp0
ppp0      Link encap:Point-to-Point Protocol  
          inet addr:33.140.12.18  P-t-P:33.140.12.18  Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
          RX packets:7 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:3 
          RX bytes:106 (106.0 B)  TX bytes:145 (145.0 B)

To set up a CDMA (EV2, EV3 radios) cellular data connection:

# Dial the connection (using /etc/ppp/peers/cdma config)
pppd call cdma

# Verify ppp0 is up
ifconfig ppp0
ppp0      Link encap:Point-to-Point Protocol  
          inet addr:33.140.12.18  P-t-P:33.140.12.18  Mask:255.255.255.255
          UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
          RX packets:7 errors:0 dropped:0 overruns:0 frame:0
          TX packets:8 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:3 
          RX bytes:106 (106.0 B)  TX bytes:145 (145.0 B)

To stop a PPP connection:

# send SIGTERM to pppd, which will cause it to hang up and exit cleanly
killall pppd