Difference Between OSI and TCP/IP Reference Models

Parameter	OSI Reference Model	TCP/IP Model
Clarification between Services, Interfaces and Protocols	OSI Model clearly distinguishes between Services, Interfaces and Protocols. Each layer performs some services to upper layers, layer interfaces tells the processes above it how to access it, and different protocols are used by different layers as per their needs until a job is not finished.	TCP/IP model does not clearly distinguish between Services, Interfaces and Protocols.
Protocol Biasing	This model is not biased for a particular set of protocols and was developed before corresponding protocols invention.	This Model was developed after inventing corresponding protocols and just was description of existing protocols.
Layers	It is a Seven Layered Model. Which are as follows : a)      Physical Layer b)      Data Link Layer c)       Network Layer d)      Transport Layer e)      Session Layer f)       Presentation Layer g)      Application Layer	It is a 4 Layered Model. Which are as follows: a)      Subnet Layer b)      Internet Layer c)       Transport layer d)      Application Layer
Entity Approaches	OSI uses Horizontal approach in creating application entities. I.e. Strict hierarchy of layers is followed by distributed applications which are constructed from common toolbox of Application Service Elements (ASEs).	TCP/IP uses vertical approach in creating application entities. i.e.  In TCP/IP each application entity contains all the functions that it needs to support a distributed communication system.