Timers

3.18. Timers

3.18.1 Timers for non call related procedures

The following timers are applied for supervising non call related procedures:

Timer	Started when	Normally terminated when	Actions after time release	Proposed value (seconds)	Possible range (seconds)
T1	ADR sent AKR sent CSU sent LCM sent LUM sent PSR sent RES sent SDR sent SUM sent SRM sent SFN sent MSD sent	ADA/ADN received AKT/AKN received CSA received LCA received LUA/LUR received PSA received REA received SDA/SDN received SUA received SRA received SFA received MSA received	Repeat the message	10	4...15
T2	T1 is started for the first time	T1 is reset due to normal received response	Terminate the procedure	60	0...300
T3	PSA sent	SRM received	Discard the PSR received. Terminate procedure	80	0...320

3.18.2 Timers for Roaming Signalling procedures

The following timers are applied for supervising the call related procedures.

Timer	Started when	Normally terminated when	Actions after time release	Proposed value (seconds)	Possible range (seconds)
T4	RNE sent	RNM rec. RNR rec	Terminate procedure	15	10...30
T5	CTE sent	CTA rec. CTR rec.	Terminate procedure	10	4...15
T6	REM sent	RIM rec. RIR rec.	Terminate procedure	15	4...30
T7	MSRN allocated	The call using this MSRN is received	Release the MSRN	20	4...30
T8	LUM sent	LUA rec. LUR rec.	Send RNR	10	4...15

3.18.3 Timer for Business group number information enquire/ response procedure

Timer	Started when	Normally terminated when	Actions after time release	Proposed value (seconds)	Possible range (seconds)
T9	BNE sent	BNM/BNR received	Terminate procedure	10	4...15

3.18.4 Timer for Call related procedures