Getting Started with OpenBTS

Chapter 5. GPRS

Mobile networks have, in many areas of the world, been reduced to being data networks. Over-the-top (OTT) services like WhatsApp and Skype only need a data pipe and participants can connect regardless of carrier. Fees between the participants are also not dependent upon geographic location, unlike local versus long-distance charges.

GPRS is much too slow to support bidirectional streaming video but can suffice for a low-quality voice call. Its speeds are ideal for email and OTT text messaging.

The world of sensors and infrastructure such as heat and flow sensors or electrical and parking meters also needs data connectivity. These low-bandwidth machine-to-machine (M2M) devices, now referred to as Internet of Things (IoT) devices, are a very common use for GPRS.

GPRS is actually not a part of GSM. It was developed after GSM had been standardized and is usually referred to as 2.5G, whereas plain GSM is 2G. OpenBTS abstracts these differences and presents a unified configuration where possible.

Enabling/Disabling

By default, the GPRS service is disabled in OpenBTS. Turn it on now by toggling the GPRS.Enable key:

OpenBTS> config GPRS.Enable 1
GPRS.Enable changed from "0" to "1"
GPRS.Enable is static; change takes effect on restart

Restart OpenBTS to apply this static key:

$ sudo stop openbts
$ sudo start openbts

Once OpenBTS has restarted, log back in to its command line and use the gprs list command to confirm that OpenBTS has set up a few channels for GPRS:

OpenBTS> gprs list ...