Here is an interesting piece by Dean Cheng of the The Heritage Foundation:
http://thf_media.s3.amazonaws.com/2010/pdf/hl1163.pdf
The abstract from Cheng's "China’s View of South Asia and the Indian Ocean":
The Indian Ocean is becoming increasingly important to China’s economic and security interests. China appears to be pursuing what has been widely characterized as a “string of pearls” strategy of cultivating India’s neighbors as friendly states, both to protect its economic and security interests and to balance a “rising India.” With Chinese influence in the region growing, it is essential that the U.S. not fall behind in the Indian Ocean, but maintain a steady presence in the region, both to signal its resolve to stay engaged and to avoid the difficulties of reentering a region.