1. There is no post of Deputy Secretary or Under Secretary in Railways. Let me explain.
(a) There are many railway officers who work in Zonal Railways, Divisional Railways and below. They are divided broadly into four categories. Operations staff, Commercial staff, Engineering staff and Signals staff. The designations of these officers would be General Manager, CPO, DPO, APO, DRM, Additional DRM, DSO, Sr. DOM, Station Superintendent, AEN, DEN, Sr. DEN, Commercial Superintendent, etc.
(b) The Ministry of Railways is known as Railway Board. Railway Board works under Chairman-Railway Board, who is the ex-officio Secretary of Ministry of Railways. Under him, there are various posts like Member (Operating), Member (Commercial), Member (Personnel) and Member (Engineering). Below the Members, there are various posts of Additional Members equivalent to General Manager of Zonal Railways.
(c) The Railway Board Secretariat functions in Directorate system. The designations of Officers are Director, Joint Director (equivalent to Deputy Secretary), Deputy Director (equivalent to Under Secretary) and Assistant Director (equivalent to Section Officer). They perform desk jobs and deal with files.
2. The general job profiles of the Joint Directors (Deputy Secretary) and Deputy Directors (Under Secretary) in Ministry of Railways are very similar in nature to the job profiles of Officers holding similar ranks in other Ministries/Departments. However, the individual job profiles would be different.
3. Almost all the Officers of Railway Board (Ministry of Railways) are appointed by UPSC.
Beware! I question everything and everybody.