hi,
i just found some valuable information this weekend at
www.informatik.hu-berlin.de/~goeller/isdn/
an introduction into gsm tracing in german
http://www.informatik.hu-berlin.de/~goeller/isdn/DieGSMDmKanaele.pdf and
the same in english
http://www.informatik.hu-berlin.de/~goeller/isdn/GSMDmChannels.pdf
it gives a rough history of GSM development, GSM network structure,
framing, encryption, coding, and services - in just 100 pages. for me it
is usefull to verify my parsing of SYSTEM INFORMATION messages. it
describes traces of the most importaint messages.
andreas