On: Cryptanalysis of GPRS Encryption Algorithms GEA-1 ...

[ronsor]

GPRS is the general packet radio service, used for (very slow) data and SMS transfer in combination with the old GSM protocol.

[gentleman11 → ronsor]

So, it encrypts sms messages and is still in use?

[giantrobot → gentleman11]

It doesn't encrypt SMS. It's over the air encryption for packet data (not calls or SMS) like WEP or WPA on WiFi. On GSM networks SMS was transmitted in leftover signaling space on voice circuits.

[secondcoming → giantrobot]

RACH: https://en.m.wikipedia.org/wiki/Random-access_channel

[ronsor → giantrobot]

IIRC "SMS over GPRS" was an optional extension