'For instance, the Su-30MKM mounts an advanced French-made IFF system , with its 'plates' situated on top of he nose section fore of the cockpit.'
Take-off Magazine, page 20. March 2017.
In the case of the Su-30MKM from Malaysia it seems from my interpretation of the above description that device front of the IRST are antennas of the French IFF( Interrogator Friend Foe) system.
However on the Su-30SM from Russia I do not think that Su-30SM has been using the French IFF system.
Otherwise, such advanced IFF systems could have been executing other functions such as ELINT (Electronic Intelligence), and the location of the antenna so close to the IRST, or even in front of it, may suggest that both systems has been working together in the same way the radar and the IRST since its legacy Su-27S/P.