03.333G security3GPPLawful InterceptionStage 2TS
Figures A3 and A4 show the interception of calls involving call hold / call waiting. Figure A3 covers the case where one pair of stublines is used per target, figure A4 covers the case where a pair of stublines is used for each target call. The mobile that receives the waiting call (A) is the target for interception.
Figure A3: Interception of call hold / call waiting – stublines per target
Figure A4: Interception of call hold / call waiting – stublines per target call