The news of 4 Su30MKI being stationed in Tezpur , which is located to the north east of gawahati in Assam was received with much joy by all the nationalist defence/strategic analysts in India.
There is no doubt that positioning the Flankers(Su30MKI) in North east will surely strenghten Indian defenses in Arunachal Pradesh and Assam.
Flanker is a very potent air domination fighter jet. The latest technology and advanced avionics put together in a single platform will make sure that this plane can take on the most formidable offensive and defensive enemy hardware. Su 30 has a large operating range and since they have been based in North East , so now they can strike deep into Central China.
The question that many people asked was that why was this step taken some time back and what message does India sends to its neighbour by taking such a step.
I second the suggestion that the recent acquisition of some hardware like Aerostat Radar and other similar sytems. The point is that Su30 is a very precious piece of military hardware and it is not a wise choice to just place such a thing close to a border with China. So once Indian Military was ready with the ways to provide proper security cover for Flankers from surprise air attack or a saturated strike of missiles, they were kept out of harms' way. Now with a cover of latest radars , Indian Fighter Jets in Assam and Arunachal are safe.
The other question is that what would 4 Su30MKI would do against an enemy with numerical superiority. I believe that even stationing 4 Su30MKI is a calculated move.
A fighter jet is a machine of no use if the supporting infrastructure in form of ground control , maintainance facility etc are not capable of supporting a particular kind of aircraft. It takes time to set up these facilities for a modern machine like SU30MKI. So IAF is trying to develop these facilities by first placing 4 SU30 and then the numbers can be increased to squadron strength without much problem.
Also till the time sufficient number of Fighter Jets can be placed , the flying crew of IAF will become familiar with the terrain and operating conditions of North East.
Since Phalcon(AWACS) has also arrived so maybe Indian Defence planners though that operating Phalcon in NOrth east will be only possible if it is provided with escorts like Su30MKI and hence having a base of SU30MKI in North east becomes required.
Overall having a large number of SU30MKI suddenly in the North East will surely send a very offensive signal to China and so for the sake of not making the tension levels of situation to rise India will slowly induct sufficient number of Flankers in North East to provide a sufficient detterence to any possible Chinese Misadventures :)