In a further sign of increasingly cordial ties between the two services, the Indian Navy's Rajput (Kashin II)-class destroyer IS Rana (D 52) has arrived in Surabaya for a bilateral naval exercise with the Indonesian Navy (Tentara Nasional Indonesia - Angkatan Laut, or TNI-AL).
The drills, which have been named Exercise 'Samudra Shakti', is seeing its inaugural edition, and is taking place from 12 to 18 November in Surabaya for the harbour phase, and waters off Java for sea phase.
Acting East keeps China's fleet from breaking out into the Indian Ocean. Friendship with Indonesia helps prevent that so India isn't defending their Andaman and Nicobar Islands line short of India proper.
Although ideally for India and Indonesia, the first line of defense is the northern part of the South China Sea.
UPDATE: Although China would love to bypass the Malacca problem by building a canal through Thailand's territory.
Thailand should refuse just to deny China incentive to control Thailand.