In layman terms , Rashtriya Rifles is a specialized organisation within the Army which is responsible for handling the bulk of Counter-Insurgency/Counter-Terrorism Operations in Kashmir. Rashtriya Rifles draws its manpower from regular Infantry and other Army Battalions where Jawans, Officers, JCO from all spheres of the Army serve for a fixed time in Rashtriya Rifles under deputation.
Some 50% of the manpower is provided by the Infantry with 10% provided by Corps of Electronics and Mechanical Engineers (EME) and Signals. The rest 40% is provided by other units in Indian Army.
The concept of Rashtriya Rifles which arrived in 1988 came as a shot in the arm for Indian Army Infantry who were pushed into CI/CT Ops to battle the situation in Kashmir which was going grave. Taking lessons from their conflicts in Sri Lanka, a specialized Quick Reaction Force was realized as the need of the time and hence Rashtriya Rifles were formed.
RR relieved Indian Army Infantry from general internal security duties who were getting eroded due to their excessive use in such roles. RR was the need of that time and even today where a dedicated force (comprising of men from Infantry and men from other roles as secondary support) can battle terrorists and militants in Kashmir.
Rashtriya Rifles is quite a flexible and versatile organisation which can be used for various ends and needs. It is a self-contained organisation in other aspects even in Intelligence where their Intel grid spreads over the valley in terms of Human Intelligence and Signal Intelligence giving deep-rooted intel about the movements and tactics used by terrorists and militants across the border.
The widespread success of RR has been due to the knowledge of terrain. It has mustered up and the the operational experience which RR carries making it perhaps the deadliest counter-terrorism force in the valley and making it a force to reckon with.
There is significant interoperability between RR and Army in Kashmir which leads to smooth functioning with RR units sometimes forming part of regular Infantry and vice versa. RR has formed fixed AOR (Area of Responsibility) in Kashmir like Romeo Force and Delta Force to meet Quick Reaction needs against militant activities which would not have been possible in case of Infantry. However now even Army has started basing its QRT in Kashmir along with RR men.
RR troopers also train upon a specific set of skills required to operate where they emphasis upon CQB, Marksmanship, Weapon Handling, Urban Warfare tactics during their pre-induction training at Corps Battle School (CBS). This makes them more effective than Infantry in CI/CT Operations and thus overall highlights the difference between them in roles and capabilities to operate in fixed AOR which differs between RR and Infantry.