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How to change MTP2 T7 timer

The Dialogic® Gate Control Element Management System alarm and event log may show the ss7 link is failed with reason as " Excessive delayed ACK(T7)", i.e.

T7 timer in the SS7 MTP2 is defined in Section 5.3.1, ITU-T Recommendation Q.703 (1996), SIGNALLING SYSTEM No. 7 – SIGNALLING LINK :

5.3.1

A timing mechanism, timer T7, shall be provided which generates an indication of excessive delay of acknowledgement if, assuming that there are at least one outstanding MSU in the retransmission buffer, no new-acknowledgement has been received within a time-out T7 (see 12.3). In the case of excessive delay in the reception of acknowledgements a link failure indication is given to level 3.

ITU Q.703 Section 12.3. recommends T7 Timer “excessive delay of acknowledgement”
T7 (64) = 0.5-2 s Bit rate of 64 kbit/s
For PCR method, values less than 0.8 s should not be used
T7 (4.8) = 4-6 s Bit rate of 4.8 kbit/s

By default, Dialogic® IMG Integrated Media Gateway sets T7 timer as 1 second for basic error correction method. This note describes a way to change the T7 timer on an IMG by using the raw API.

Procedure:

In the IMG, the MTP2 T7 timer is PPL Timer id 2 in the PPL Component MTP2 TXC (PPL id 0x0026). 

The attached example changes the MTP2 T7 timer to 2 seconds on SS7 link:

00 11 00 cf 00 01 01 00 01 09 02 ss ll 00 26 01 02 00 c8

00 0c 00 d0 00 01 00 00 01 01 01 00 00 01