Indian Diplomacy

Indians are successful in wooing Iran, Arabs and Israel. Lesson from Indian diplomacy: never put all eggs in one basket.

http://www.bits.de/public/documents/iran/iran080206.pdf
However, Iran reportedly turned to India in 1993 to help develop batteries for the three Kilo-class submarines Iran had bought from Russia. The submarine batteries provided by the Russians were not appropriate for the warm waters of the Persian Gulf, and India had substantial experience operating Kilos in warm water

http://indianexpress.com/article/opinion/columns/india-iran-chabahar-port-deal-narendra-modi-2829537/
The first step in Indian-Iranian regional cooperation was taken during the visit of then Indian Prime Minister Atal Bihari Vajpayee, who was in Tehran in April 2000, followed by Muhammad Khatami’s visit to India in January 2002 (as a guest at the Independence Day function). They were boosted by the signing of the New Delhi Declaration which laid out the principles of cooperation in defence, including the training of Iranian military personnel by India.

http://www.indiandefencereview.com/interviews/india-iran-defence-cooperation/ 
Defence ties between India and Iran further evolved post signing of a Memorandum of Understanding (MoU) on defence cooperation in 2001. It was in the same year that Indias Defence Secretary, Yogendra Narain, met his Iranian counterpart, Ali Shamkani, and supposedly discussed arms sales to Iran including Indian Konkurs anti-tank guided weapons and spare parts.5 India and Iran are hopeful that New Delhi will become a source of conventional military equipment and spare parts for Iran, provide expertise in electronics and telecommunications and hold joint training exercises with Iranian armed forces. Tehran also seeks New Delhi to provide combat training for missile boat crews as well as simulators for ships and submarines and purportedly anticipates that India provide midlife service and upgrades for fighters, warship, and subs in Indian dockyards. 


http://www.cacianalyst.org/publications/analytical-articles/item/7799-analytical-articles-caci-analyst-2003-2-12-art-7799.html 
2003: BACKGROUND: Last December, a high-level defense delegation from India visited Iran. The Indian team also evaluated the proposed development of a transport corridor from India to Afghanistan and Central Asia through Iran and submitted its findings in a report to the Defense Ministry. The Indo-Iranian defense cooperation agreement was signed on January 19 in Tehran by Admiral Madhavendra Singh, Indian Navy chief and chairman of the Chief of Staff Committee, and Rear Admiral Ali Shamkhani, Iranian Minister of Defense and Logistics of the Armed Forces.