Thu, 17 May 2007

Telstra NextG and Sierra Wireless Aircard 875.

At my day job we needed to connect our Ubuntu based appliance to Telstra's NextG broadband wireless network using the Telstra supplied Sierra Wireless Aircard 875. These things are PCMCIA cards but internally, they present as a USB serial device. According to lsusb: 


  Bus 006 Device 002: ID 1199:6820 Sierra Wireless, Inc.

Kernels after about 2.6.20 will recognize this device and automatically load an appropriate driver and set up three /dev/ttyUSB* devices. For kernels that don't recognize the card do: 


  modeprobe usbserial vendor=0x1199 product=0x6820

Once the /dev/ttyUSB* devices are set up correctly create the files /etc/ppp/peers/telstra_aircard_875 and /etc/ppp/peers/telstra_aircard_875_chat.

New file : /etc/ppp/peers/telstra_aircard_875. The username and password below need to be there but can be anything, including the exact same ones as I have here. 


  lock
  crtscts
  modem
  hide-password
  noauth
  /dev/ttyUSB0
  460800
  defaultroute
  replacedefaultroute
  noipdefault
  usepeerdns
  noipdefault
  user anyname
  password anypassword
  noauth
  connect '/usr/sbin/chat -v -f /etc/ppp/peers/telstra_aircard_875_chat'

New file : /etc/ppp/peers/telstra_aircard_875_chat The XXXX below should be replaced with the Telstra supplied PIN number that should be unique for each card. 


  ABORT BUSY
  ABORT 'NO CARRIER'
  ABORT VOICE
  ABORT 'NO DIALTONE'
  ABORT 'NO DIAL TONE'
  ABORT 'NO ANSWER'
  ABORT DELAYED
  ABORT ERROR
  TIMEOUT 20
  ""
  "AT+CPIN?"
  READY-AT+CPIN=XXXX-OK "AT&F"
  OK "ATE1"
  TIMEOUT 20
  OK "ATDT*99***1#"
  CONNECT \d

Finally, edit the file /etc/ppp/pap-secrets, and add the following entry. Again, this needs to be there, but will be the same for everyone. 


  # For telstra_aircard_875
  user@telstra.internet * telstra

Getting connected should now be as easy as: 


  pppd call telstra_aircard_875

One of the slightly odd things about this card and Telstra's NextG network is that if the four digit PIN number isn't sent during the CHAT session the CHAT session will connect and pppd will try to negotiate an IP address but get no response, eventually timing out. Anyone who experiences this problem should first make sure that the service has been activated from the Telstra end (possibly by making sure it works under windoze) and then turn on debugging for both chat and pppd.

Posted at: 20:27 | Category: Tech | Permalink