SAP NOTE: DIFFERENCE BETWEEN R/1, R/2, R/3

DIFFERENCE BETWEEN R/1, R/2, R/3

R/1:

SAP R/1-> 1-tier architecture.
where all 3 layers [presentation layer+ application layer+ database layer] installed in single server.

R/2:

SAP R/2-> 2-tier architecture.
where [presentation layer] in one server and [application layer+ database layer] installed in second server.

R/3:

R/3-> 3-tier architecture.
where all 3 layers installed separately in server.