Testing of M2M devices is not standardized, so there are no publications covering such testing. Typically, M2M device developers, beyond regulatory testing, test products in the field. If the GSM modem is certified (regulatory and operator), the M2M device needs to be tested to ensure the application properly handles conditions like:
* cell reselections, if the device is mobile
* network latency (i.e. wireless latency is different from wired)
* recovery from network timeouts, outages, maintenance, etc.
* recovery from device anomalies (lock-ups)
Depending on your device's application, there are a number of scenarios that need to be evaluated.
Also, see the following document for information on developing your application: http://m2m.com/docs/DOC-1007