The GSM Security Map compares the protection capabilities of mobile networks.

Networks are rated in their protection capabilities relative to a reference network that implements all protection measures that have been seen “in the wild”. The reference is regularly updated to reflect new protection ideas becoming commercially available. Networks, therefore, have to improve continuously to maintain their score, just as hackers are continuously improving their capabilities.

Mobile network security report: Belgium, December 2014 :
http://gsmmap.org/assets/pdfs/gsmmap.org-country_report-Belgium-2014-12.pdf

Un article sur le sujet : http://geeko.lesoir.be/2015/01/02/base-ne-protege-pas-suffisamment-ses-clients/