During the communication between mobile and ISDN telephone equipment, the signalisation takes place in three signalling areas. On the local network the ISDN protocol DSS-1 is used. On the long-distance network (i. e. between local exchange, trunk exchange and mobile switching center) SS#7 works using the IUP and MAP protocol whereas between BTS and Mobile, using the radio interface  and logical channels, Call-Control-Messages are conveying signals like those in the ISDN-D-Channel.
To test the  end-to-end properties of the Channel "telephone- mobile" it is necessary to trace both, the ISDN-D-Channel and the GSM-Dm-Channel.
For instance, you would like to test the period of time between the lifting of the handset of the ISDN-telephone and the ringing of the mobile. In this case you must measure the time between the occurrence of SETUP on the ISDN-D-Channel and the occurrence of ALERTING on the GSM-Dm-Channel.

To do so, you need a tracetool to take the time of the SETUP-Message and you need a tracetool to catch the GSM-CC-trace, too. A description of taking an ISDN-trace is given above on this web site. To catch the GSM-CC-trace the author used a SAGEM OT 760 M Trace Mobile and the software OT Drive PC v.2.3.3.
The trace got recorded and exported via EXEL in TEXT mode. The  so called Interlayer 1 Format of the Layer 2 frames got converted by means of the Program GSMViewLight written by Sebastian Göller. (GSMViewLight translates only CC-Messages).
To get the same source of time, both trace tools reside on the same computer.

In the following the GSM-trace is shown:                                     MobileSite.txt
To calculate the difference of time you need the ISDN-trace too:   ISDNSite.txt

The difference of time between SETUP(ISDN site) and ALERTING (GSM site) is 6.229 seconds