I dont have step by process, but have a look at below information abt authorization groups:
The access protection system must ensure that only authorized individuals have access to the system and to particular data. For achieving precise application security concerning authorization and to protect confidential data against unauthorized access it is very important to focus on the use of authorization groups.
The authorization group allows extended authorization protection for particular objects. The authorization groups are freely definable. They usually occur in authorization objects together with an activity.
The table that contains all authorization objects is TOBJ.
The table that contains all activities is TACT.
The table that contains definition of all authorization groups is TBRG.
TBRG -- Contains all authorization groups and gives information about relation between authorization object and authorization group. The description of the authorization groups is defined in table TBRGT.
The field name for authorization group -- BRGRU -- is used to make additional restrictions on authorizations /e.g. for document maintenance/. In authorization objects and authorization checks, there are fields which are checked to verify user authorizations. Customizing objects are combined in authorization groups, and the authorization group is one of the two authorization fields, for example, in authorization object S_TABU_DIS which is in the object class BC_A (Basis - Administration). This object is for displaying or maintaining tables. It controls access using the standard table maintenance tool (transaction SM31), enhanced table maintenance (SM30) or the Data Browser (SE16), including access in Customizing.
Authorization object S_TABU_DIS has the following fields: DICBERCLS - Authorization group, maximum field length is four characters; and ACTVT - Activity (02: Add, change or delete table entries, 03: Only display table contents).
Generally, SAP standard tables are assigned to authorization groups. These assignments can be changed. You can then assign tables manually to a suitable authorization group. To do this, start Transaction SM30 for maintenance view V_DDAT, and create an entry for each of these tables. In V_DDAT is stored the assignment of Tables/Views to Authorization Groups. V_DDAT is cross-client; therefore, it can be viewed and used in all clients.
Note: If you don't make a selection, all tables maintained in Customizing transactions are assigned to authorization groups.
Creation of authorization groups depends upon the requirement. In some cases authorization groups must exist in a custom table before they can be used. This is true for table authorization groups (authorization group in table TBRG assigned to tables in table TDDAT via transaction SE54) and user groups (created in transaction SUGR). In some cases authorization groups are merely created when they are assigned to the object in a standard maintenance transaction (e.g. vendor master data, customer master data, material master data etc.) In other cases the authorization group has an optional validation table that is used in search helps but no where else (ABAP programs in table TPGP and TPGPT, report writer authorization groups (via table TBRG) etc. Authorization groups are essentially labels that you assign to objects (tables, programs, master data etc.) that allow authorization checks for access to the objects with the label.
I hope it gives you some details abt their creation.
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