Hi All,

I'm newbie to SCCM, I want to know how the configuration manger hierarchy lies in real time.

Like If we have 25k clients on an average how many CAS,PS,SS&DPs.

If you explain a real time scenario that will be help full to me.

Thanks in Advance. 

25k clients? Don't use a CAS. A standalone hierarchy can handle up to 150.000 clients. A DP can handle up to 4.000 clients, but there are many factors to consider (number of locations, clients per location, wan speed etc)

For client scalability numbers, please review https://technet.microsoft.com/en-us/library/gg682077.aspx

For site role deployment planning, please review https://technet.microsoft.com/en-us/library/gg712282.aspx