As
@pmaitra, renamed the thread and added the option of solution for our defense, here goes my view..
1. Get the basics of defense --------- >
A. Tools to fight ( Tanks, Gunships, Helos, Arty, Special tools for infantry to fight in that terrain that is from basics )
B. Infrastructure, ( Road and Rail ( Meter / Short gauge ), Bunkers of all kind, Airbases, Helipads, Barriers, Mine fields etc )
C. Surveillance, ( Ground / Air surveillance, Intelligence gathering aircraft / Vehicle / platform / Human source )
D. Pre-Planned Strategy ( One should plan when and where to strike and how deep a counter attack should be done to stop further thrust of enemy )
2. Get Practical --------- >
India - China border are of mountains, Some are narrow and some are large valleys, One should always keep in mind about locations of enemy reserves and transport infrastructure specially of China, If such nodes are hit PLA machines and men will be stopped for time being, China infrastructure in Indian media is ' Overrated ' China dont have many roads ( Though which are made can take 100tons and quite wide ) nor proper Railway nodes close to our borders, the roads have tunnels and bridges which are very vulnerable to PGM / Cruise missiles / Bombers / tactical BM ( Everything ( Excluding Nukes ) should be thrown off to cut of these nodes as these are vital for our success ), If hit it will delay all kinds of supplies hence more time for us to conduct counter attacks.
There is also a very good advantage over TAR region that Long range SAM are ineffective due to valleys, TAR is vast and there are many ways to get inside with fighters jets hence Chinese infrastructure more vulnerable, China also lack Airbase compare to India all along LAC, Its major bases are far east beyond Burma, though because they are over TAR there surveillance is better than us..
Bottom line is,
Snatch your Enemy Tactical Positions and at the same time deny its reinforcements and supplies, force your enemy into submission, In case of attack on India, We must suffocate our enemy and push it back to a distance from where we can be confident that we are well dug in and enemy cannot carry another large scale thrust..
Some of my research on eastern front ( N.E area ) ============>>
Equipment of both Armies over Eastern Front ( Only N.E ) :
http://defenceforumindia.com/forum/indian-army/16694-indian-army-vs-pla-lac-information-thread.html
PLAAF preparation over Eastern sector along LAC ( Only N.E ) :
http://defenceforumindia.com/forum/military-aviation/17393-plaaf-offensive-combat-readiness-against-india.html