Notice Period ( Different For Different Employees)

I am working in a MNC. When I joined the company my offer letter stated that I need to serve a notice period of 3 months once I complete my probation period. However, for all the new joiners, starting form this year, the notice period is reduced to 2 months. This is applicable for employees who are at the same department and are at the same level as I am in. My question is whether it is possible for an employer to use two different notice periods for employees who have same designation and are from same department?

It is possible since he contract employment will be with an individual employee. However, matters of probation, confirmations and notice period form part of the policy as a whole..Therefore please very with your HR department whether the reduction in notice period is applicable to all employees irrespective of their date of joining.
B.Saikumar