I could not find the meaning of the term "restrictate" used in your query. Whether it is the private sector or public sector, the power of the employer to fire an employee is inherent with their power to hire them. However, it is restricted by the terms of the contract of employment as well as the provisions of the laws applicable to the employee.
If the position held by the employee is other than the cadre of a workman as defined under the Industrial Disputes Act, 1947, the employer can terminate their services by following the unilateral termination clause provided in the contract of employment. Nevertheless, there should be some reasonable cause for such a drastic action by the employer; otherwise, such a clause would not escape judicial scrutiny as it would be opposed to public policy under Section 23 of the Indian Contract Act, 1872.