Specifications

AT Command Set for L55 Platform 2003-11-21
Copyright  Siemens AG 2003 All Rights Reserved Page 118 of 131
2.8.2.2 Defining Quality of service for a CID
Quality of Service (QoS) is a special parameter of a CID which again consists of several parameters.
The QoS consists of
• the precedence class
• the delay class
• the reliability class
• the peak throughput class
• the mean throughput class
and is subdivided into "requested QoS" and "minimum acceptable QoS".
All parameters of the QoS are initiated by default to the "network subscribed value (= 0)", but the QoS
itself is set to undefined. Use the AT+CGQREQ or AT+CGQMIN command to define a QoS.
e.g.:
AT+CGQREQ=1,2
OK // overwrites the precedence class of QoS of CID 1 and sets
// the QoS of CID 1 to be present
A following read command will response
AT+CGQREQ?
+CGQREQ: 1,2,0,0,0,0
OK // all QoS values of CID 1 are set to network subscribed
// except precedence class which is set to 2
AT+CGQREQ=1
OK // set the QoS of CID 1 to not present
After defining a CID it could be activated. To activate a CID use
AT+CGACT=1,2
OK // activate CID 2
If the CID is already active, the mobile immediately returns OK.
If no CID is given, all CIDs defined will be activated by means of
AT+CGACT= // NO CID and NO STATE given
OK // all defined CIDs will be activated
If no CID is defined the mobile returns ++CME ERROR: invalid index
Remark: If the mobile is NOT attached via AT+CGATT=1 before activating, the attach is automatically
done by means of the AT+CGACTcommand.
After a CID has been defined and activated, it can be used using AT commands as in the following
example:
AT+CGDATA=PPP,1
CONNECT // the mobile is connected using the parameters of CID 1
AT+CDATA=
CONNECT // the mobile is connected using default parameter
The mobile supports Layer 2 Protocol (L2P) PPP only.
Remark: If the mobile is NOT attached by means of AT+CGATT=1 and if the CID is NOT activated
before connecting, the attach and activate is automatically done by means of the AT+CGDATA
command.